Spinal implants and methods for the placement thereof are disclosed herein. In one variation, the implant includes a support member, a proximal retention member, and a distal retention member. The support member is configured to be disposed between adjacent spinous processes. The proximal retention member has a first configuration in which the proximal retention member is substantially disposed within a proximal portion of the support member, and a second configuration in which a portion of the proximal retention member is disposed outside of the support member. The distal retention member has a first configuration in which the distal retention member is substantially disposed within a distal portion of the support member, and a second configuration in which a portion of the distal retention member is disposed outside of the support member.