Despite still being in the Under-17 age group in 2006, Stander was named captain of the SWD team for the premier high schools rugby union tournament in South Africa, the Under-18 Craven Week, held in Stellenbosch.

He led from the front, scoring two tries against the Leopards,[8] one try against KwaZulu-Natal[9] and a hat-trick in their final match against the Griffons[10] to finish as the tournament's top try scorer.

[21] After high school, Stander moved to Pretoria to join the academy of Currie Cup side the Blue Bulls for the 2009 season onwards.

Before he experienced any game-time in a Blue Bulls jersey, however, he was named in the South Africa Under-20 team to compete at the 2010 IRB Junior World Championship in Japan.

[32] Despite making two further appearances for the Under-21s and scoring a try for them against the Leopards,[33] he represented the Under-19s in the play-offs, but the team failed to get past their trans-Jukskei rivals the Golden Lions at the semi-final stage.

[39] He captained them to a 73–0 victory over Scotland,[40] before being involved in South Africa's first ever defeat in a pool match at the Junior World Championships, as they lost 35–42 to Australia.

[47] He made a further four starts and two appearances as a replacement, but with players like Danie Rossouw returning from international duty, dropped back into the Blue Bulls U21 team.

[67] After a second appearance off the bench against the Cheetahs a week later,[68] Stander made his first start in the competition in a home defeat to New Zealand side the Blues.

[69] With Dewald Potgieter and Deon Stegmann missing the majority of the season through injury, Stander firmly established himself in the side and started a further ten matches in a row.

[75] Despite a call-up to train with the South Africa national team as they prepared for the 2012 Rugby Championship, Stander was not included in their final squad[76] and instead continued to represent the Blue Bulls in the Currie Cup.

[81] The team finished in fourth place on the log[82] and Stander's final match in a Blue Bulls jersey was their 3–20 defeat to the Sharks in the semi-finals.

[83] In June 2012, Stander signed a deal to join Irish province Munster on a two-year contract at the end of the 2012 Currie Cup Premier Division season.

Stander, with very limited English, was denied entry by the doorman and, not knowing any of his teammates phone numbers and very little money on his person, found himself lost.

Fortunately, Stander recalled that one of his new teammates, Barry O'Mahony lived near the a guide dogs facility in Cork, and was able to get a taxi to his home.

[95] Stander made his Heineken Cup debut on 12 October 2013, coming off the bench against Edinburgh in Munster's opening pool game.

[105] Stander started in Munster's first 2014–15 European Rugby Champions Cup game against Sale Sharks on 18 October 2014, earning the Man-of-the-Match award in the 27–26 away win.

[146] On 22 April 2017, Stander made his return from the ankle injury sustained during Munster's quarter-final, starting in the semi-final against defending champions Saracens and scoring a try, though it wasn't enough to stop the English side from winning 26–10 in the Aviva Stadium.

[153] Stander captained Munster in their 39–22 away win against Southern Kings on 7 April 2018, scoring a try in the match that was played in Outeniqua Park in his hometown of George.

[155] One week later, Stander scored Munster's only try in their 10–10 draw against Exeter Chiefs in Sandy Park during the sides' opening 2018–19 Champions Cup pool 2 fixture.

[174] In his final game for the province in Thomond Park, Stander captained Munster to a 31–27 win against Cardiff Blues in round 4 of the Pro14 Rainbow Cup on 28 May 2021.

[179] On 7 February 2016, Stander made his debut for Ireland, starting against Wales in their opening match of the Six Nations and earning the Man-of-the-Match award in 16–16 draw.

[193] On 18 March 2017, Stander made a late switch to Number 8 for Ireland when Jamie Heaslip pulled out of the game against England during the warm-up.

[194] Following his performances in the tournament, Stander was nominated for the 2017 RBS 6 Nations Player of the Championship award, alongside teammate Conor Murray.

[198] Stander started four games for Ireland as they won a Grand Slam in the 2018 Six Nations Championship, featuring off the bench against Italy and scoring a try against England.

[208][209] Stander started in Irelands' 32–20 home defeat against England in the opening round of the 2019 Six Nations Championship on 3 February 2019, though he went off injured during the game.

[235][236] Two days after winning his 50th cap for Ireland, Stander made a shock announcement that he would be retiring from rugby at the end of the 2020–21 season, citing a desire to raise his young daughter around his family in South Africa, to leave the game whilst still in good form, and to reduce the burden placed on his young family by a professional rugby players career.

[237] Ireland captain Johnny Sexton expressed his surprise at Stander's decision, whilst also heaping praise on his international teammate.

[245][246] On 10 June, Stander made his second appearance of the tour when he replaced Ireland teammate Seán O'Brien in the match against Crusaders in AMI Stadium.

[249] On 27 June, in the final mid-week fixture, Stander started against the then-defending Super Rugby champions Hurricanes in Westpac Stadium.

[256] He was also named an honorary Limerick man at the Limerick Person of the Year awards in April 2021,[257] and appeared on The Late Late Show in May 2021, discussing in particular the famous figure of 8 that the Ireland players formed in tribute to Anthony Foley ahead of their historic first ever win against New Zealand in 2016, and the support he received from the vast majority of the public when faced with criticism of being a South African playing for Ireland.