A modular interspinous system is shown having a first plate, a generally opposing second plate and a modular insert that may be removably or permanently secured to the first plate. The first plate has a coupling means, coupler or connection system in the form of a screw that may be permanently or non-permanently docked or supported in the first plate. The modular insert is adapted, sized and shaped to expose at least a portion of the screw thread of the screw and that portion may cooperate with at least one mating female thread in the second plate, thereby enabling a user to rotate the screw in order to drive the first and second plates towards or away from each other and, for example, into compression with bone.