Al holds the all-time PRO12 record for most appearances as captain of any team, playing as skipper in 86 league games to date. He has also led the team in 35 Heineken Cup matches.
Glasgow Warriors head coach, Gregor Townsend told glasgowwarriors.org: “This was an easy decision to make. Al is an inspirational leader and does so much for the club both on and off the pitch.
“He sets an example to others and he has undoubtedly played a huge role in the growth of the club over the last few years.
“This appointment will provide continuity for the club as we look to build on our third place finish last season.”
Al said: “I am extremely proud to have been named captain of the club for the eighth season in a row.
“I feel hugely privileged to be able to play for this club and captaining the side is very special.
“It's a great honour for me to have been chosen once again and I'm looking forward to leading the team in the RaboDirect PRO12 and Heineken Cup next season.
“There are some new faces in the squad and a lot of competition for places so hopefully we can have a good season.”