  We show a general decomposition theorem in Baer *-rings. As a consequence the
vast majority of decompositions known in the algebra of bounded Hilbert space
operators are generalized to Baer *-rings. There are also results which are new
in the algebra of bounded Hilbert space operators. The model of summands in
Wold-S{\l}oci\'nski decomposition in Baer *-rings is given.
