MAG Sydney (otherwise known as Mature Age Gay Sydney or MAG) is a social club for gay and bisexual men and our supporters. We care for each other, sharing friendships and affection with people in similar situations to lead as full a life as possible.

MAG was founded in 1991 by Steve Ostrow through a project of ACON (AIDS Council of NSW, Australia). Steve described it as "a peer support, social, and educational group targeting mature age men forty and up who have sex with men, regardless of how they choose to identify themselves".

MAG is one of the largest gay organizations in Australia, measured by attendance at regular meetings. We meet on the second and last Saturday of every month with a typical attendance of approximately fifty members at every meeting. There is no lower age limit for members — we focus on the needs of gay men over forty. Most MAG members are between fifty and eighty, with some stalwarts over ninety.