Colin Hillman played and coached first class rugby in the XV-side game but was best known for his Sevens expertise.
He coached Wales at Sevens tournaments around the world including the Commonwealth Games.
In 2002, he became the Spanish national Sevens coach but at the start of last season, he was appointed technical advisor to the Wales Sevens squad and is credited by Paul John and his coaches and players as having had a major influence on their preparations and success at last season's Rugby World Cup Sevens in Dubai. He died in July after a long battle with pancreatic cancer.
Sevens has recently become an Olympic sport, with the competition entered into the 2016 Games in Rio de Janeiro.
WRU president Dennis Gethin presented the caps to the Hillman family and the Rugby World Cup winning Sevens squad at the pre-match reception at the Millennium Stadium today.
He also made a presentation to Rhodri Morgan who attended his last Wales international as First Minister.
WRU chairman David Pickering said, "Awarding caps to Wales Sevens internationals represents the increased significance of Sevens rugby to our game. The historic decision has recently been made to return rugby union to the Olympic Games, in the form of Rugby Sevens and there is no doubt about the increased importance of Sevens around the world, with players, coaches and administrators recognising the attractions of the shortened game.
"Colin Hillman was an inspirational leader in the field of Sevens. I played under him in 1987 when he led us to the Dubai Sevens title so it is symbolic that some 22 years later, he was involved in the WRU's first world trophy success, at the Dubai Rugby World Cup Sevens.
"It is fitting that we should also pay tribute to First Minister Rhodri Morgan today as four years ago he asked us to fly the flag for Wales through our Sevens team, not only through achieving success on the field, but by carrying Wales' corporate identity around the world. On behalf of all of Welsh rugby, I wish him well in his retirement."
WRU Head of Rugby, Performance and Development Joe Lydon said, "Colin Hillman did so much to put Welsh Sevens on the map. As coaches, we came up against each other on the Sevens circuit, including in a Hong Kong Sevens semi-final and he was not only a great coach but a fantastic human being.
"In awarding caps to Sevens players, we want to also recognise all those who have helped develop Wales Sevens especially David Rees and Gareth Baber, Paul John's predecessors, and David Jenkins who has been Wales Sevens team manager since the WRU re-joined the IRB Sevens circuit in 2005."
Wales Sevens head coach Paul John said, "Colin was such a guiding influence on Sevens rugby in Wales, and had a huge impact on us as a playing and coaching group last season, and our successful Rugby World Cup Sevens campaign. He would be very pleased to see the developments in Wales Sevens, including the facilities we now enjoy, the decision to contract core players, and to recognise Sevens players in this way."