Buffon signed with French club Paris Saint-Germain at the age of 40 in 2018, where he was used in a rotational role with Alphonse Areola; he won the Trophée des Champions and Ligue 1 title in his only season with the team, before returning to Juventus the following year.

Following his performances during the 2006 World Cup, where he kept a record five clean sheets, Buffon won the Yashin Award and was elected to the Team of the Tournament, an honour he also received from UEFA after reaching the quarter-finals of the 2008 and the final of the 2012 European Championship.

[9] Despite offers from Bologna and Milan,[10][nb 2] Buffon began his career with the Parma youth system in 1991, at the age of 13, as the team's coach Ermes Fulgoni was struck by his physical qualities.

[36][37][38] Buffon later said that there had been an initial possibility for him to join Roma, but they signed Ivan Pelizzoli instead, and although negotiations were ongoing with Barcelona, he chose Juventus because his father convinced him he would be likely to achieve his ambition of winning the Scudetto.

Juventus were knocked out in the quarter-finals of the Coppa Italia to eventual champions Inter, and finished the Serie A season in a disappointing seventh place, only qualifying for the 2010–11 Europa League through the playoff round.

[166] The following week, Buffon was nominated for the 2015 UEFA Team of the Year,[167] also making his 100th appearance for Juventus in European Club Competitions in a 1–0 home win over Manchester City on 25 November.

In the process, he set a new personal best in the top flight, and the outright sixth-best unbeaten streak in the history of the Italian league, after going 746 minutes without conceding a goal in Serie A, overtaking Morgan De Sanctis and Marchegiani.

[238] On 19 August, Buffon made history by saving the first Serie A penalty awarded via VAR in a 3–0 home win over Cagliari in the club's opening league match of the season.

[256][257] After Juventus lost 3–0 to Real Madrid at home in the first leg of the Champions League quarter-final on 3 April, Buffon helped Juventus keep a 3–0 away lead in the second leg on 11 April, until the 93rd minute when he was sent off for dissent after a confrontation with referee Michael Oliver who awarded an injury time penalty to Real Madrid; Szczęsny was forced to be substituted in, with the resulting penalty kick converted by Cristiano Ronaldo for a final 4–3 aggregate loss.

[263] On 13 May, Buffon won his record seventh straight Scudetto, following a 0–0 draw with Roma in Juventus' penultimate match of the season while an unused substitute;[264] with this league victory, he became the first player ever to win nine Serie A titles.

[270] On 30 June, the final day of his Juventus contract, Buffon bid the club farewell with a post on Twitter: "Seventeen years in black and white [officially] end today.

[282] On 12 February, Buffon kept his 50th Champions League clean sheet in a 2–0 away win over Manchester United, becoming only the third goalkeeper to reach this milestone after Iker Casillas (57) and Edwin van der Sar (51).

[310] On 17 June 2021, after days of speculation following his departure from Juventus, newly relegated Parma announced the return of Buffon through a short video posted on the club's official Twitter account.

[321] Buffon came on in the 31st minute and made notable saves under snowy conditions in a 1–1 away draw, including an important stop from a Dmitri Alenichev shot, only being beaten by a Fabio Cannavaro own goal.

Buffon played every minute of Italy's 2002 World Cup campaign,[12] keeping a clean sheet in the opening match against Ecuador,[336] and saving a controversial penalty against co-hosts South Korea in the round of 16, which was not enough to stop the under-performing side from being eliminated by a golden goal in extra time.

[353] Buffon wore the captain's armband for Italy for the first time under manager Roberto Donadoni, in a 2–0 home win over Georgia in a Euro 2008 qualifier, due to the suspension of regular skipper Fabio Cannavaro.

[358] Buffon kept a clean sheet against France in the final group game, and garnered praise in the media for a notable save against Karim Benzema, as Italy won 2–0 to advance to the quarter-finals.

On 11 October, prior to Italy's 3–0 win in a European qualifier against Northern Ireland, Buffon received a commemorative cap and medal from UEFA to mark his 100th international appearance; regarding his achievement, he commented: "I feel I'm entering the football nobility today and I'm happy to celebrate this milestone while still playing".

Although both Buffon and Spanish counterpart Iker Casillas had managed to keep a clean sheet throughout the match, neither goalkeeper was able to stop a penalty in the shootout; the lone miss, by Leonardo Bonucci, was hit over bar.

[381][382] In the 2014 FIFA World Cup qualifying fixture against the Czech Republic, at Juventus Stadium in Turin on 10 September 2013, Buffon equalled Cannavaro as the Italy national team record appearance holder, with 136 caps.

[413] He returned to the starting line-up for his nation's round of 16 fixture against Spain on 27 June, making a crucial injury time save on Gerard Piqué to earn his third consecutive clean sheet of the tournament, as Italy avenged their Euro 2012 final defeat with a 2–0 victory over the defending champions.

Since his emergence as a precocious talent in his youth, Buffon was renowned for his consistent performances throughout his career, and received praise from managers, players, as well as both present and former goalkeeping colleagues, for his concentration and calm composure under pressure, as well as his work-rate, and longevity.

[129][445][448][451][452][453][454] He was described as "an agile, strong, and commanding shot-stopper, who is hugely experienced at the highest level" and "an accomplished and well respected keeper"[455][456][457][458] with an "[e]xcellent positional sense, courage, power and class".

[459] Buffon was praised for his athleticism, his "outstanding shot-stopping",[460] his acrobatic dives, and his quick reflexes,[456][461] as well as his ability to produce decisive saves,[462][463] despite being a tall, large and physically imposing goalkeeper.

In his prime, Buffon was a talented, complete, brave, aggressive, and often instinctive and frenetic goalkeeper, who was recognised for his speed, prowess, and anticipation when coming off his line in one on one situations, as well as his confidence, goalkeeping technique, reactions, and ability to get to ground quickly to collect, parry, or even challenge for the ball with his feet; when playing in teams that relied upon high defensive lines and a zonal marking system, he often functioned as a sweeper-keeper, frequently rushing out of his area to clear the ball or face opponents who had beaten the offside trap.

His confidence in possession allowed him to play the ball out from the back on the ground to his defenders and start swift counter-attacks, as well as find his teammates further up the pitch or out on the wing with deeper kicks with his right foot.

After struggling with a series of injuries between 2008 and 2010,[507][508] Buffon effectively adapted his style of goalkeeping to the physical effects of ageing, while also modifying his diet and training regime, and as a result, developed into a less spectacular, but more efficient, calm, and reflective goalkeeper;[444][445][446][475][484][485] despite the loss of some of his physical strength, explosiveness, speed and mobility, he continued to excel at the highest level due to the consistency of his performances, as well as his positioning between the posts, tactical intelligence, decision-making, and his ability to read the game and organise his defence.

[466][475][479][485][509] In addition to his goalkeeping abilities, Buffon was singled out for his charisma, strong mentality, discipline in training, vocal presence in goal, and leadership,[444][448][510][511] and was described as "a key dressing room personality".

[601][602] In September 1999, Buffon faced heavy criticism and severe disciplinary sanctions for bearing the Italian fascist slogan Boia chi molla ("Who gives up is a scoundrel") handwritten on a T-shirt under his goalkeeping jersey, which he wore and showed during media interviews after a match against Lazio.

[604] In 2000, Buffon risked a four-year prison sentence for falsifying a high school accounting diploma in order to enroll for a law degree at the University of Parma, and ultimately paid a 6,350,000 Lire fine in 2001; he later described the incident as his biggest regret in life, stating that it had been a dishonest gesture.