[en] The phenomenology of polarization and spin effects in inclusive processes is studied. These effects are examined using the triple-Regge formalism valid at large s/M² and large M², however the connection between this region and the small M² region via finite-mass sum rules (FMSR) and M²-duality is emphasized. The two distinct types of polarization effects [i.e., type I = (a/sub up-arrow//sup b/ → c/sub up-arrow/); type II = (a /sup b up-arrow/ → c)] are discussed separately and in detail. Examples and predictions are given and existing data examined. Other observables in inclusive processes are also mentioned briefly