This article summarizes the results of a previously published two-volume investigation on the biblical meaning and the historical development of these two fundamental concepts, including a further discussion on contributions to this subject which have appeared in this journal (see below section 4). In contradistinction to K. McDonnell a different catholic position is given here: The term ‘Spirit-baptism’ as used within the Pentecostal-charismatic movement means neither the sacramental grace of initiation nor the setting-free of it, but is a term on the experiential level denoting a special kind of infilling with the Holy Spirit in our time. It is not ‘normative’, but— although very widespread—something that the Holy Spirit ‘distributes as he wills’. Thus, the early Pentecostal two-stage model is far more appropriate than the sacramentalistic interpretation. In that sense Spirit-baptism— normally with the gift of tongues—is a special grace of God.