By far the most popular and avidly enjoyed benefit of Mensa membership is participation in a Special Interest Group, or SIG, through correspondence with members everywhere who share your special interest, via the Internet and through SIG newsletters. There are several SIGs currently operating within the Malaysian Mensa Society and hundreds more overseas and on the Internet accept International Members. There is no limit to the number of SIGs that you can join. If you are a member of Mensa and cannot find a SIG for your particular interest, please contact the National SIG Coordinator who can assist you in either locating one overseas or start a new SIG.

SIG coordinators are all volunteers and a joining fee is sometimes charged to cover the costs of Newsletters and activities. There are currently some 400 SIGs around the world which members may join: with diverse pursuits ranging from serious (eg Military Heritage, Financial Intelligence, Abuse Survivors...) to hobbies and interests (Cross Stitch, Computers, Adventure & Exploration...) to the frivolous and zany (eg. Absurd SIG, Creative Mischief, Party, Alfred Hitchcock...).