Michael Phelps is the most decorated Olympian of all time, with his record 22 total Olympic medals entering his fifth Games in 2016. He owns a record 18 gold medals, two silvers and two bronzes.
His illustrious career will come to a close at the end of the 2016 Rio Olympics and the world will bid farewell to Phelps. Watch each of his Olympic races below and see post-race and reflective comments from Phelps, his longtime coach Bob Bowman and teammates he’s taken his Olympic journey with.
Michael Phelps at the 2000 Sydney Olympics
At the 2000 Sydney Olympics, when he was just 15 years old, Phelps placed fifth in his only individual event: the 200m butterfly.
In their own words: Phelps' longtime coach Bob Bowman later said looking back on the race that Phelps "screwed up. [He] went out too fast."
Michael Phelps at the 2004 Athens Olympics
At the 2004 Athens Olympics, Phelps became the second man to win eight medals at a single Games. He captured six gold and two bronze.
2004 Athens 400m individual medley, gold
Michael Phelps wins his first-ever Olympic medal, a gold, on the first day of swimming competition at the 2004 Olympics in Athens.
In his own words: “I've thought about this every day for my whole entire swimming career," Phelps said then. "Standing on the Olympic podium is something I've always wanted to do. It's an amazing feeling. Since I was a little kid I've been waking up every day hoping to win a gold medal.”
2004 Athens 4x100m freestyle relay, bronze
Ian Crocker, Michael Phelps, Neil Walker and Jason Lezak combine for a bronze medal in the 4x100m freestyle relay, behind South Africa and the Netherlands.
2004 Athens 200m freestyle, bronze
The "race of the century" saw Australia's Ian Thorpe, the Netherland's Pieter van den Hoogenband and Michael Phelps face off in the 200m freestyle.
In his own words: "It was my best time by half a second," Phelps told media. "When you have a star-studded field like that and those guys are going so fast, it makes it all so exciting. One of the things I've wanted to do is to race [Ian] Thorpe in a freestyle event before either one of us is done."
2004 Athens 4x200m freestyle, gold
Michael Phelps, Ryan Lochte, Klete Keller and Peter Vanderkaay captured gold ahead of the Australians in the 4x200m freestyle relay in Athens.
In his own words: "That's probably the most exciting race I've ever been a part of," said Phelps. "I don't think I've ever celebrated like that in my entire life."
2004 Athens 200m butterfly, gold
Michael Phelps looked to improve on his fifth-place finish in the 200m butterfly from Sydney. He did so in a big way, capturing gold in what was then Olympic record time.
2004 Athens 200m individual medley, gold
Michael Phelps and Ryan Lochte finish first and second in the 200m individual medley in Athens, an event they continue to battle in throughout the years.
2004 Athens 100m butterfly, gold
Michael Phelps wins his first of many Olympic golds in the 100m butterfly at the Athens Games.
In his own words: "That race is like something I've dreamed about every single day leading up to this," Phelps said at the time. "I can't say this enough: This is a dream come true. But it means even more with [teammate] Erik [Vendt] winning the silver medal.”
2004 Athens 4x100m medley relay, gold
Michael Phelps swam in the preliminary heats of the relay, which secured for him whatever medal the American team went on to win in the final. He ceded his spot to teammate Ian Crocker, and the U.S. men went on to win a gold medal.
In his own words: "We came into the meet as a team," Phelps said, explaining his decision to media, "and we're going to leave it as a team. It's tough to give up the relay; it really is. But Ian is one of the greatest relay swimmers in the world."
Michael Phelps at the 2008 Beijing Olympics
En route to becoming the first swimmer ever to capture eight golds in a single Olympics in 2008, Phelps set seven world records.
2008 Beijing 400m individual medley, gold
Michael Phelps opened his Beijing Olympic program with a gold medal in the 400m individual medley. Then-President George W. Bush gave him a thumbs-up sign from the stands.
In his own words: "I told Bob [Bowman] that this would be my last 400m IM, so I've got to go out there and get a good time."
2008 Beijing 4x100m freestyle relay, gold
The French men's relay team told media before they race they were going to smash the Americans. Michael Phelps, Garret Weber-Gale, Cullen Jones and Jason Lezak answered in a big way.
In their own words: "Michael knows we didn't do this for him," Lezak, one of the 2008 team captains, told media. "He was just a part of it and we were a part of it. Whether he wins eight gold medals or not, it wasn't going to be our responsibility for that to happen."
2008 Beijing 200m freestyle, gold
Michael Phelps improved upon his bronze-medal finish from the Athens Olympics in the 200m freestyle to win gold in Beijing.
2008 Beijing 200m butterfly, gold
Michael Phelps swam the 200m butterfly semifinal about 15 minutes after winning the 200m freestyle gold medal. The following night, he set a world record and won gold in the 200m butterfly despite his goggles flooding with water.
In his own words: "As soon as I dove in, they filled up," he said of his goggles. "I was more or less trying to count my strokes, hoping I'd be dead on at the turns. I'm disappointed because I know I can go faster, but there was nothing I could do. I handled it the best way I could."
2008 Beijing 4x200m freestyle relay, gold
Michael Phelps claimed the title of greatest Olympian of all time with his 11th career gold medal. He won gold in the 4x200m freestyle relay alongside Ryan Lochte, Ricky Berens and Peter Vanderkaay.
In his own words: "I'm almost at a loss for words," Phelps said of breaking the career record. "To be in the same group with the greatest Olympians who ever lived, to have the most golds in history is unbelievable. After the [200m butter]fly, I was trying to focus, but I just kept thinking, 'Wow, the greatest Olympian of all time.' That's a pretty cool title."
2008 Beijing 200m individual medley, gold
Michael Phelps repeated as Olympic champion in the 200m individual medley at the Beijing Games. Again, teammate Ryan Lochte was also on the podium, this time with a bronze.
2008 Beijing 100m butterfly, gold
Michael Phelps defended his Olympic gold from Athens in the 100m butterfly by a margin of 0.01 seconds.
In his own words: "When I chopped the last stroke, I really thought it cost me the race," Phelps said of the extremely tight finish. "But it happened to be the exact opposite. If I had glided, I would have been way too long. I ended up making the right decision, trying to take a short, fast stroke to get my hand on the wall first."
2008 Beijing 4x100m medley relay, gold
Michael Phelps, joined by Aaron Peirsol, Brendan Hansen and Jaszon Lezak, won gold in the 4x100m medley relay at the Beijing Olympics.
In his own words: "Everything was accomplished," said Phelps, summing up his history-making 2008 Olympic experience. "I will have the medals forever."
Michael Phelps at the 2012 London Olympics
At the 2012 Olympics, Phelps became the most decorated Olympic athlete with a record 22 medals: 18 gold, two silver and two bronze. He earned six of those medals at the London Games, four golds and two silvers.
2012 London 400m individual medley, fourth place
Michael Phelps was wrong about the 2008 Beijing 400m individual medley being his last. He raced to a fourth-place finish in the event at the 2012 London Olympics.
In his own words: "It was just a crappy race," Phelps said. "I felt fine the first 200, then I don't know. They just swam a better race than me, a smarter race than me, and were better prepared than me. That's why they're on the medal stand." Four years later, Phelps reflected and called the race a "mistake."
2012 London 4x100m medley relay, silver
Nathan Adrian, Michael Phelps, Cullen Jones and Ryan Lochte combined for a silver medal behind France in the 4x100m freestyle relay in 2012.
In his own words: "We tried to get ourselves into as much open water as we could. We had four great guys to get up there and swam as fast as we could. We were the ones that the coaches thought were going to have the best shot. We went out there and raced. That's all you can ask."
2012 London 200m butterfly, silver
Michael Phelps raced the 200m butterfly in an Olympic final for the fourth – and what he thought would be the last – time in London. South Africa's Chad le Clos beat him to the wall, relegating Phelps to a silver medal.
In his own words: "I would have liked a better outcome in the 200m butterfly. Obviously it was my last one and I would have liked to win but...it wasn't a terrible time."
2012 London 4x200m freestyle relay, gold
Michael Phelps earned his first gold of the London Games alongside 4x200m freestyle relay teammates Ryan Lochte, Conor Dwyer and Ricky Berens. It marked Phelps' 15th career Olympic gold and 19th Olympic medal.
In his own words: "I thanked those guys for helping me get to this moment," Phelps said. "I told those guys I wanted a big lead. I was like, 'You better give me a big lead going into the last lap,' and they gave it to me. I just wanted to hold on. I thanked them for being able to allow me to have this moment."
2012 London 200m individual medley, gold
Michael Phelps became the first swimmer to three-peat in an event, winning gold in the 200m individual medley at three consecutive Olympics.
In his own words: "To be the first to three-peat is something pretty special to me,” Phelps said, adding, “It’s cool to add it to the résumé.”
2012 London 100m butterfly, gold
Michael Phelps won his third consecutive Olympic gold in the 100m butterfly in London. He won each of the three consecutive gold medals in the 100m butterfly by a combined 0.28 seconds. At the time, he thought it was the last individual swim of his career.
In his own words: "I didn't have a good finish and didn't have a good turn but I am just happy to defend that title," he told media. "It's a good way to finish my last individual swim ever."
2012 London 4x100m medley relay, gold
Michael Phelps swims what he believed to be the last race of his career and won gold alongside Matt Grevers, Brendan Hansen and Nathan Adrian in the 4x100m medley relay.
In his own words: "It’s kind of weird looking at this and seeing ‘Greatest Olympian of All Time,’” Phelps said, adding: “I finished my career the way I wanted to. I think that’s pretty cool.”