A support device for use in supporting a user's spine while in a seated position, including lower, top and intermediate sections merged smoothly in a rigid piece. The device extends the entire length of the user's spine from occipital region to coccyx, and includes lateral support for maintaining a centered spinal position. The device preferably sits on the seat of a chair or automobile seat and leans against the back of the seat to support the user's spine. The intermediate section of the device is preferably narrow to sit flush with the user's back between the shoulder blades (scapulae) and allowing the user to rotate to either side in the seat. The support is preferably constructed with a flocked or fabric-covered foam exterior over a rigid plastic armature.