There are two types of membership: non-contributing and contributing memberships.
Anyone who agrees with the principles of SPI should consider signing up for a non-contributing membership. SPI's goal is to reflect the intent of the free software community and to represent the views of its membership.
Contributing memberships are open to those who participate actively in the free software community. These members also have voting power in the organization. In order to apply for a contributing membership, you have to sign up for a non-contributing membership first.
The membership committee has created a set of guidelines which define who is eligible for a contributing membership.
Questions regarding the membership process should be directed to the membership committee.