This paper presents a completion procedure for proving termination of term rewrite systems. It works as follows. Given a term rewrite system R supposed to terminate and a term rewrite system T used to transform R, the completion builds an auxiliary term rewrite system S, the system transformed of R by T. The termination of S and T associated with a property called local cooperation implies the termination of R. If the process terminates this provides a mechanical proof of the termination of R.