Veteran game-show host Jack Barry and his producing partner Dan Enright, along with Robert Noah and Buddy Piper, created Concentration, but others working at Barry & Enright Productions also contributed to the show's development. The full end credit roll after the NBC takeover had a title that read "Based on a concept by Buddy Piper".

The creation involved the combination of two key creative concepts: the children's game of matching cards, and the use of a rebus puzzle that was revealed as matching cards were removed from the board. In place of the playing cards, the game board featured a board consisting of 30 "trilons", or three-sided motorized boxes, with numbers on the first of their three sides; prizes, that were to be matched, on the second; and "puzzle places" on the third. The gradual matching of card pairs slowly revealed elements of the rebus, a picture puzzle described below.

The rebus form is centuries old and has been used in various forms. The most popular contemporary form prior to Concentration involved pictures, letters and numbers as well as plus and minus signs to add or delete parts of a word or phrase (e.g., WICK + E + PEA + D + UH)

The member of the Barry-Enright development team responsible for the development and art direction of the puzzles was Norm Blumenthal, who later became the original series' producer. He simplified the rebus form for television, allowing only plus symbols, and subsequently devised all of the puzzles seen on the original series. In his version of a rebus puzzle, which became Concentration's standard, a rebus is a puzzle made up of a combination of pictures, letters, words and numbers connected by plus signs. When solved, it gives a well-known title or phrase. For instance:

• A picture of a convict (CON)
• A plus sign
• A picture of a penny (CENT)
• A plus sign
• A picture of a serving tray (TRAY)
• A plus sign
• A picture of a human leg, shin highlighted (SHIN)

CON + CENT + TRAY + SHIN (CONCENTRATION).

Although many graphic artists contributed to the on-air renderings of the puzzles, only one, Bernard Schmittke, was with the series throughout its entire 1958–1991 history.

Two contestants (one a returning champion) sat before a board of 30 squares. Each square was composed of a trilon that concealed the rebus, names of prizes, and special squares.

One at a time, the contestants called out two numbers. If the prizes or special action did not match, the opponent took a turn. However, if the contestant did match, whatever prize was printed on the card was placed on a board behind the contestant; or, he/she could perform an action. The second number had to be called out within a certain time limit, otherwise the contestant's turn ended. It was also permissible to pass on one's turn. This usually happened during the course of a game if a contestant called out a prize card that had been orphaned as the result of a wild card match (see below).

More importantly, a match also revealed two pieces of the rebus, which identified a person, phrase, place, thing, etc. The contestant could try to solve the rebus by making one guess or choose two more numbers. There was no penalty for a wrong guess; even if he/she was wrong, he/she kept control. Usually, a contestant waited to solve the puzzle until he/she had exposed a good portion of the rebus through several matches. In rare instances, the puzzle was solved with only a few clues showing.

Also included were two or three joke or gag prizes (such as a banana peel or a tattered sock). Over the years, the gag prizes included some creatively bad puns and wordplay. These actually served as protection against matching the forfeit cards upon which he/she might stumble.

Special squares

In addition to the prize cards, there were the following action cards:

• Wild card: Provided an automatic match. In the original game this left the natural match "orphaned," only able to be matched by the other Wild Card, of which there were only two on the board. If the contestant matched the same prize to both Wild Cards, a check mark was placed next to the prize on the contestant's board, and that contestant would win two of that prize if s/he solved the puzzle.

Contestants uncovering both Wild Cards simultaneously also won a bonus that was theirs to keep regardless of the game's outcome. Originally, this was $500 but late in the run was changed to a new car.

• Take One Gift: Appeared on two cards in each game. If a contestant matched them, he/she could take his/her choice of any of the prizes listed on their opponent's prize board. Of course, the game had to be won to receive all prizes listed on his/her prize board.

• Forfeit One Gift: Appeared on six cards in each game. If a contestant matched two of them, he/she had to forfeit one prize to his/her opponent.

• Bonus Number: Appeared on four cards in many games. A contestant who matched them got a chance to select three numbers as opposed to the usual two. This was used only in the 1973–1978 syndicated edition hosted by Jack Narz. (See the section below dealing with these editions.)

Solving the puzzle

If a contestant solved the puzzle, he/she won all of his/her accumulated prizes. If there were no legitimate prizes in the rack, he/she was awarded $100. The loser forfeited all his/her gifts accumulated in that game, but still received token parting gifts as well as a copy of the show's home game. There was no bonus round in the original version of the show.

Occasionally, a game ended with only two prize cards left on the board, which because of the wild cards often did not match. In such instances, the unmatched cards were turned over to reveal the entire puzzle, and the contestant who made the last match was allowed one guess to try to solve it first. If he/she guessed incorrectly, his/her opponent was allowed to make one guess. If both guessed incorrectly, the game ended in a draw. A new game was played and each contestant was allowed to carry over a maximum of three prizes.

Occasionally, a game could not be completed due to time constraints. A sequential two-tone sound resembling a doorbell would be heard signaling time was up for that episode, and play was suspended. Play would resume at the start of the following episode with the board reset to the point where time was called. A new rebus puzzle was substituted and the prizes remained the same, but were behind different numbers.

Champions continued until they either were defeated or had won 20 games.

Concentration remains the longest-running game show on NBC and held the record for longest continuous daytime run on network television until it was eclipsed in April 1987 by the CBS daytime version of The Price is Right (beginning September 4, 1972). Concentration is currently the fourth longest-running daytime/syndicated game show behind The Price is Right and the syndicated versions of Wheel of Fortune (1983–present), and Jeopardy! (1984–present).

Concentration was an NBC in-house production, apart from the earliest episodes. As a result of the 1950s quiz scandals, the network purchased the rights to Concentration and three other games (Twenty One, Dough Re Mi and Tic-Tac-Dough) from producers Barry and Enright. NBC/Universal still holds exclusive rights to both the format and extant episodes of Concentration; however, due to Financial Interest and Syndication Rules, this version is owned by CBS Television Distribution.

Concentration's original host was Hugh Downs. The show was produced and broadcast live at 11:30 am Eastern on weekdays in black-and-white, and quickly became the most-watched daytime series in NBC's lineup. The announcer was Art James, who sometimes served as a substitute host and later became a game show host in his own right. The series was produced in NBC's Studio 3A which now houses NBC News and MSNBC.

The series then moved to 11:00 am and slowly introduced color broadcasts. For a picture puzzle game whose rebuses were designed and painted in monochrome, this required some design changes: The colors of the numbered cards might otherwise interfere with the colors used on the rebus, a critical issue for contestants playing in the studio and for viewers who played along at home. During this period, the series was produced in NBC's Studio 6A. Hugh Downs, by this time also an anchor correspondent on NBC's Today Show, remained host, and the announcer became Jim Lucas, who also worked on NBC's local New York radio station, WNBC-AM. In September 1965, the show moved to 10:30 am where it would spend the remainder of its run on NBC.

In January 1969, Downs stepped down to devote his entire attention to Today. Bob Clayton, who had succeeded Jim Lucas as announcer, took over the hosting duties but in March, NBC set him aside in favor of Ed McMahon due to advertiser pressure. However, Clayton returned in September and remained host until the series ended. On the Monday following Concentration's cancellation on NBC, Clayton became the announcer for The $10,000 Pyramid on CBS. NBC staffer Wayne Howell replaced Clayton in the announcer's booth during his tenure as host.

Special features

Seen daily for nearly 15 years, and consistently one of the most popular series on NBC, the original series included many special features. Among the series' popular special features:

• The Envelope and its Mysterious Contents — The winning contestant opened a sealed envelope and read its message aloud (as if he/she were the show announcer). Generally, it mentioned an inexpensive prize and further reading proved it to be an expensive prize, such as large amount of cash or a new car.
• The Cash Wheel — A contestant spun a carnival wheel containing various dollar amounts with a top prize of $2,000.
• Christmas shows featured children from United Nations countries. Secret Santas included Joe Garagiola, Victor Borge, and other celebrities. Proceeds went to C.A.R.E., which built two schools in Africa from funds raised by the series (Blumenthal and Downs received awards from the organization for the proceeds).
• International Salutes — All prizes in these games were from the specific country saluted. For example, a salute to Mexico had contestants wearing sombreros, Downs dressed as a matador, and model Paola Diva playing a colorfully costumed señorita driving a mule-driven cart.
• An annual Boy Scout Show, saluting famous Americans who were scouts. Den Mothers and Scouts played the game and won prizes for themselves and their troops. Girl Scout shows also became an annual event.
• The Challenge Of Champions — Beginning in 1963, Concentration inaugurated a tournament of champions, which pitted the top four contestants of the previous 12 months in a best-of-seven tournament (styled à la the World Series). The grand prize was $1,000, a trip around the world and a special trophy dubbed "The Connie", modeled after Auguste Rodin's The Thinker. One of the participants in the very first tournament was Brooklyn Dodgers pitcher Ralph Branca, who won 17 games on the show.

Throughout the competition, participants, including Downs, Clayton, and Blumenthal, wore blue blazers with the show's logo, known as the "mystery logo," embroidered in gold on the breast pocket. The "mystery logo" blazers continued to be a part of the host's wardrobe until the show ended in 1973.

During another contest (c. 1970), home viewers could win a prize based on the initial of their last names corresponding to a number on the board. To enter the contest, one merely had to send a postcard to the address given. These postcards were placed in a rotary drum and Clayton would draw a card and read the name. If the prize card was for a gag prize or "forfeit one gift", the home viewer received $100. If it was "take one gift", a $250 prize was awarded. If it happened to be a wild card, the home viewer won $500. The contest was held at least once a week, and frequently with several drawings per show.

On one episode during this time, a viewer from Oklahoma won a motorboat. Host Bob Clayton made the mistake of asking "What could he possibly do with a boat in Oklahoma?", after which the show was inundated with brochures on Oklahoma lakes. In fact, most Oklahoma lakes are man-made in response to the Dust Bowl.

Through nearly all of the original series' run, the program was produced by Norm Blumenthal. He not only created every one of the 7,300 puzzles used on the show (with no repeated puzzles), but also every puzzle utilized in all 24 editions of the Milton Bradley home game.

Prizes

The prize values on the original series were deliberately much smaller than those of Barry and Enright's other games, especially the big-money games (not just their own) implicated as part of the 1950s quiz show scandals. The winnings were kept at a low amount on purpose to avoid any suggestion that it was also tainted. When the network took over production shortly after the series began in 1958, NBC maintained this policy, although this may have been for reasons unrelated to the scandals.

Usually, there was at least one prize worth more than $1,000. However, nearly all the other prizes were worth less than $500, with many in the $10–$100 range. A board of prizes rarely totaled more than $2,000–$3,000 and champions rarely took home more than that in merchandise during their stay (though some longer-reigning champions approached $10,000).

Additionally, there were countless gift certificates, travel trailers, airplanes, swimming pools, furniture, kitchen appliances (large and small), rooms of furniture, clothing, stereos and televisions, fantastic nights out on the town and virtually any other item seen in any mail-order catalog. One history of the original NBC version reported the total prize giveaway at $10,000,000.

Cancellation

For most of its run, Concentration faced sitcom reruns on CBS and local programming on ABC affiliates, easily dominating them in the ratings. However, in September 1972, CBS launched The New Price is Right at 10:30/9:30 and drained off more than half of the Concentration audience. Rather than move the game, NBC concluded that it had reached the end of its life and cancelled it in March 1973.

While the first puzzle on the debut was "It Happened One Night", the last puzzle on the finale was "You've Been More Than Kind". After Clayton said a final goodbye, the credits rolled over a rendition of "Auld Lang Syne".

Baffle, a Merrill Heatter-Bob Quigley production hosted by Dick Enberg, replaced it at that time slot and ran until March 29, 1974.

Five months after NBC canceled Concentration, a daily syndicated series debuted on local stations. The project was a joint venture of syndicator Jim Victory, Mark Goodson-Bill Todman Productions, and NBC, which retained the rights to the show. The syndicated Concentration and its followup Classic Concentration are the only two programs that Goodson-Todman/Mark Goodson Productions produced that did not originate "in house," meaning that they were not created by people working for the company. The show premiered on September 10, 1973 and ran for five years. Jack Narz was host, with Johnny Olson serving as announcer. This version of Concentration was produced at Metromedia Square in Hollywood, and aired primarily on NBC stations that had carried the original series.

Rules

Two new contestants competed each day, with no returning champions; and games did not straddle episodes as on the network version (as some affiliates only broadcast the program one evening a week). For the first two years, the basic game was identical to the NBC version with the addition of four "head starts" that revealed half the locations of four prizes on the board. In addition, the gag prizes disappeared and only one pair of "forfeit one gift" cards remained; three pairs of "take one gift" cards were hidden on the board.

Concentration's board had become very colorful. The 30 numbers (now larger) were in red with yellow backgrounds and red frames. Many prize, Forfeit, Take, and wild card spaces had actually come from New York with the original board and were reverse-printed (white lettering on a black background). The rebus was in full color on a sky blue background.

The cash prize if a contestant solved the puzzle with no prizes on his/her side of the board was increased from $100 to $250. The bonus for calling two "Wild Cards" on the same turn reverted to $500 as opposed to a new car as last offered by NBC; the bonus was once again theirs to keep regardless of the game's outcome. In addition, unlike in the original NBC version, the contestant no longer received the opportunity to match the wild card spaces and reveal four parts of the puzzle. Prizes that were once only consolation prizes on the NBC series and other game shows became the prizes on the board. If the board had no more matches and no one solved the puzzle (or if time was running out), the remaining parts were revealed and a contestant rang an electric buzzer to give his/her solution.

If there was time for a third game, a "money game" was played. This game was basic Concentration with no head starts. The board now contained matched amounts of foreign currency with the usual Take, Forfeit and wild card spaces. When a player matched a certain variety of currency, Narz noted the equivalent in American dollars. If a contestant solved the rebus before time ran out, s/he was awarded the money in American currency. If time ran out, however, the contestant credited with more money was declared the winner and kept the money they had matched.

Double Play

The champion played a new bonus round called Double Play. The contestant was given ten seconds and shown a rebus puzzle. If the contestant was able to solve the puzzle before time expired, the clock was stopped and he/she won $100. A second rebus puzzle was shown and, if the contestant was able to solve it within the time remaining, he/she won a new car.

Beginning in fall 1977, contestants determined their Double Play prize from a nine-square board containing four pairs of matching prizes (one of which was always a car) and a wild card. The contestant called numbers until a prize was matched, and choosing the wild card meant the contestant played for all prizes revealed up to that point. It is not known what would have happened if the wild card was chosen first.

The music for a Double Play win has also been used since the 1970s on The Price is Right as pricing-game music in which the prize is a car. Many other Price cues were used on Concentration as well, such as for the "head starts" and Double Play prize descriptions.

Changes

For the show's third season that fall, the board was completely rebuilt with a smooth high-speed mechanism that made the trilons almost fly around. The first of many changes to come in the game arrived with four "Bonus Number" cards (eliminating one prize pair and one of the take one gift pairs). If a contestant matched two "Bonus Number" cards or combined one with a wild card, then the next time they selected two numbers which failed to match, they were permitted to select a third number.

Another change with the new revival was the reversal of the contestant and board locations, oddly common among game shows originally produced in New York and moved to the West Coast. The contestants now sat stage-right, with the board positioned stage-left. There was no emcee's podium and from the series' debut through the spring of 1976, Narz was mainly off-camera during the game, standing in the center of the stage and standing between the contestants only after a win or at the show's end, just as hosts did on the original NBC version. Beginning in the fall of 1976, he began regularly standing between the two contestants during the playing of the game. The prize tote board consisted of the two doors that were originally part of the New York set, but cut down and made permanently set boards in the new set. A single bell chime sounded whenever a match was made.

Beginning in the fall of 1975 and continuing through the spring of 1976, more rules were changed to speed up game play: The "Forfeit One Gift" spaces were done away with outright. The board now hid two "Free Look" spaces. Selecting one instantly revealed that particular portion of the rebus and allowed the contestant who selected the space the option of taking a guess at the puzzle. Two more wild card spaces were added to the board and the prize for matching them was reduced to $250. Contestants now called a third number in the first game if the first two picks did not match (later changed to having a third pick in both games). All of the remaining original trilon cards were scrapped and replaced with new graphics. The rebuses were also made shorter and easier, all trends that later made up Classic Concentration.

Cancellation

Despite these changes, the show's ratings fell and many stations (including former flagship WNBC in New York) moved the show to either pre-dawn hours or other non-prime time access slots and dropped it in Spring 1976. Some independent stations then picked up the show for its final two years.

On September 8, 1978, the second version of Concentration aired its final episode and left the airwaves, with the exception of several markets who opted to air reruns for an entire season until fall 1979.

In 1985, Mark Goodson Productions was set to launch an hour-long game show block with a new syndicated version of The Price is Right and a revived Match Game. However, after concerns about Gene Rayburn's advancing age were raised (he was 67 years old at the time), the Match Game revival was scuttled and Goodson sought permission from NBC to try Concentration again. A pilot was shot in 1985 with Orson Bean hosting but failed to sell. Although Goodson went forward with his plans to launch The Nighttime Price Is Right without a companion program, both he and NBC did not give up on Concentration and a new series was developed.

The new series, which became known as Classic Concentration, debuted on NBC on May 4, 1987. Alex Trebek (who at the same time was also hosting Jeopardy! which he still does today) hosted and Diana Taylor was the series' prize model. In July of that year, Mark Goodson's daughter, Marjorie Goodson-Cutt, replaced Taylor and remained for the entire series. Gene Wood was the announcer, with Art James substituting for him for several weeks in 1991. The new Concentration ran once again at 10:30 AM EST and remained in that slot for its entire run.Classic Concentration's final new episode aired on September 20, 1991, but reruns continued to air for two more years and ended on December 31, 1993.

Early in the run, Alex would wear suits and then in mid 1988 until summer 1989, he would wear sweaters or short sleeve shirts or semi-formal shirts and then back to suits.

Gameplay

Main game

This version featured a 25-space computer-generated gameboard, with in-studio contestants viewing on a large-screen TV placed off stage.

Most games had three wild cards, although some games used only one or two. Choosing two wild cards in one turn earned the contestant a $500 bonus, and if a third was chosen in the same turn the bonus doubled to $1,000. In 1989, a second cash bonus was added to the board with the introduction of the "Cashpot", an accumulating jackpot that started at $500 and added $100 for each game it was not claimed. As with the other prizes, cash bonuses could only be won if the contestant solved the rebus. When a wild card match was made, the natural match was also located resulting in three puzzle parts being revealed, or more if multiple wild cards were found in one turn.

In the earliest episodes of Classic Concentration there were no "take one gift" cards on the board. In November 1987, a pair of green slides which read "TAKE!" were added. Upon making a match, the contestant was given a token which could be used to take one of their opponent's prizes. In February 1988, a second set of red TAKE! cards were added, but a contestant had to match like-colored TAKE! cards in order to claim them from the board. Unlike past versions of Concentration, the TAKE! did not have to be used immediately, and a contestant could use the card(s) to take a desired prize or protect an already-claimed prize after making a match at any time during the round.

In the event time ran short during a game, the puzzle was revealed one square at a time, in numerical order. The first contestant to buzz in with a correct answer won the game. If incorrect, the contestant was locked out, and the rest of the puzzle was revealed for the opponent to receive a free guess. If both contestants were incorrect, either of them could buzz in after the host began reading the puzzle, giving clues to the solution of the puzzle until one contestant guessed correctly.

Originally after a puzzle was solved, Alex would go to the board and explain the puzzle, then in late 1988 until the series ended in 1991, the winning contestant would go to the board and explain the puzzle.

Bonus round

The bonus round, dubbed the "Winner's Circle", was played for one of eight cars that were displayed in the studio. The contestant was shown a board of 15 numbered panels, behind which seven of the eight cars had matching pairs; the eighth was always used as a decoy. Contestants were given a base time of 35 seconds to play the round, with five seconds added for each time the round was not won. If a contestant managed to match all of the cars, the last car he/she matched was the car won. Each time a car was won, the clock was reset to 35 seconds for the next round.

Early in the show's run, a contestant could win the game and play the bonus round up to five times before being retired. Later, champions were only retired after winning a car.

Occasionally, "Five Bonus Car Seconds" was a prize appearing in the main game. Any contestant who solved a rebus and had matched this prize earned five additional seconds in the bonus round.

Returning champions

In the beginning of the run, each match consisted of one game with the winner advancing to the bonus round. A losing contestant left with parting gifts except if their game was interrupted, in which case he/she would return for the first game on the next show.

On July 4, 1988, the format was changed into a best-of-three match, with the first contestant to solve two rebuses winning the match and playing the bonus game. Unlike most game shows that tend to straddle when playing a best-of-three format, Classic Concentration had each match and bonus game fit into one complete show. The first game was split over the first two segments, with the second game taking up the third segment, as well as the third when needed. For the third game, no prizes were offered; the puzzle was simply revealed in order of numbers until a contestant buzzed in with the correct answer. The bonus round was played during the fourth segment of the show.

From July 2, 1990 onward, the format returned to having the winner of the puzzle play the bonus game. However, contestants could continue to play until losing twice or winning a new car.

Audience Game

If there was time remaining during some shows, an audience member preselected before taping began played the bonus round for up to $500. Instead of the names of cars, dollar amounts were hidden behind the 15 numbers. The audience member was given 60 seconds and kept any amounts matched, which accumulated as they went along.

Tournament of Champions

Starting in 1988 and continuing annually until the end of first-run episodes, there was a Tournament of Champions. The contestants who won the bonus round in the shortest amount of time were invited back to play for a more upscale car and $10,000.

The winner of a standard front-game round played the bonus round, at first using the base time of 35 seconds. If a contestant was able to win a car within the time limit, he/she provisionally won the last car matched, plus his/her time became the new "base time" (e.g., if a contestant cleared the board in 29 seconds, all future contestants had to complete the round in less time to be eligible to win). At the end of the tournament, the contestant who completed the bonus round in the shortest time won the grand prize.

The Milton Bradley Company introduced the first commercial version of Concentration in 1958 and subsequently released 24 editions of the game until 1982. Owing to common superstition, these releases were numbered 1–12 and 14–25, skipping 13. It was tied with Password as the most prolific of Milton Bradley's home versions of popular game shows, and was produced well after the Jack Narz era ended in 1978 (albeit without ever including elements from that version).

Pressman Games published two editions of the Classic Concentration home game in 1988. More recently, Endless Games has released two versions of Concentration since 1998. The Endless version were modeled similar to Classic Concentration home game with the rebuses designed by Steve Ryan, who created puzzles for Classic Concentration.

Two computer versions of Classic Concentration were released by Softie for MS-DOS systems, as well as the Apple II and Commodore 64. A Nintendo Entertainment System version was also released by GameTek. Tiger Electronics also marketed a hand-held version of the game in 1999 using the Narz-era theme and the 1960s–1978 logo.

There were also books based on the TV shows. Three issues for the original were released in 1971, written and designed by Norman Blumenthal. Each issue of this collection featured 36 rebus puzzles, 30 standard and six "super puzzles".

In 1991, the book "CLASSIC CONCENTRATION: The Game, The Show, the Puzzles" was written by puzzle designer Steve Ryan (and plugged on the air). This book showcased 152 full color rebuses designed from the Classic Concentration TV show with the first 48 of them simply showing the entire, exposed rebus and the other 104 showing a partially revealed game board, followed on the next page by the entire rebus. The book also showcased a lengthy Concentration history and an introduction by executive producer Mark Goodson.

A video slot machine based on the 1958-1973 version was released for American casinos by Bally Gaming Systems.

In 2007, Reflexive Arcade released a downloadable version of Concentration based on the Classic Concentration format and bonus round with newer puzzles and prizes. In 2008, Glu Mobile released a mobile version of Concentration based on the PC downloadable version, with the look of the original 1958–1973 series.

Some kinescope recordings of the 1958–1973 version are held at the Library of Congress. Shokus Video offers a Hugh Downs-hosted tournament episode from 1967.

Concentration is one of only three Barry-Enright game shows known to have foreign adaptations, the others being Tic-Tac-Dough and Twenty-One.

United Kingdom

Australia

Several versions aired from 1959 to 1967 (with a nighttime version airing until 1961) with Philip Brady, then in the 1970s with Lionel Williams, and then again in 1997 with Mike Hammond as host. The 1960s version aired on the Nine Network, while the latter versions aired on the Seven Network.

Colombia

Concéntrese aired during the 1970s (from Unicentro shopping centre) and 1980s.