The 34-year-old scrum-half won 76 caps in a Test career which began in 2010 and is Scotland’s second highest points scorer with 714.
Laidlaw said: “Emotionally, this decision was incredibly tough however, when I reflected on what I have learned from playing Test level rugby and where Scotland is as a national team, it makes sense.“Captaining your country to victory is the stuff of childhood dreams. To say I will never again stand in the tunnel, filled with nerves, alongside my rugby family and lead my team-mates out on to the pitch at BT Murrayfield, is incredibly hard.“While my body and heart could continue playing, my head tells me that it’s time to let the team rebuild. In terms of where Scotland is now, they are in a position to spring forward and I cannot wait to give them my full support from the stands.“To the Scotland coaches and backroom staff over the years who dedicate hours behind the scenes to prepare the team collectively and as individuals, I thank you. To the people who have helped me achieve my dreams: my team-mates, my parents, sister, family, close friends and my incredible wife, Rachel, and our sons, I will be forever thankful for all the support you have shown me over the years; you have stuck by me through thick and thin.“I’d also like to thank Scottish Rugby and the staff behind the scenes who have both supported me as captain and a player and enabled the team to perform in front of capacity crowds. And finally, a massive thanks to the Scotland supporters both in Scotland and abroad for sharing the rollercoaster ride of international rugby with me. Your support was always appreciated, from messages on social media to being at the stadium, or just stopping to chat on the street. I look forward to supporting the team alongside you all at BT Murrayfield soon. Alba gu bràth.”Laidlaw began his career with his local Jed-Forest club before seven years with Edinburgh between 2007 and 2014. He then joined Gloucester before a move to France with Clermont Auvergne. His last appearance in a Scotland jersey came, as captain, in the 28-21 defeat to Japan at the recent World Cup. He captained the side in the 2015 World Cup in England after narrowly missing out on selection for the 2011 tournament in New Zealand.