Disclosed are interbody fusion spacers, or cages, for insertion between adjacent vertebrae. The cages may have integrated and deployable anchors that allow the cage to have a first, insertion configuration characterized by a reduced size to facilitate insertion through a narrow access passage and into the intervertebral space. Once implanted, the anchors of the cages may be deployed to enable better fixation to bone. The cages may promote fusion to further enhance spine stability by immobilizing the adjacent vertebral bodies.