The main thesis of the article is that language change is only partially subject to criteria of functionality and that, as a rule, opposing forces are also at work which often correlate directly with psychological and sociopsychological parameters reflecting themselves in all areas of linguistic competence. We sketch a complex interplay of horizontal versus vertical, deliberate versus nondeliberate, functional versus antifunctional linguistic changes, which, through a variety of processes have an effect upon the languages concerned, whether in the lexicon, the grammar, the phonology or the phonetics. Despite the overall unclarity regarding the notion of functionality in language, there are clear cases of both functionality and antifunctionality. Antifunctionality is deliberately striven for by groups of speakers who wish to distinguish themselves from other groups, for whatever reason. Antifunctionality, however, also occurs as a, probably unwanted, result of syntactic change in the acquisition process by young or adult language learners. The example is discussed of V-clustering through Predicate Raising in German and Dutch, a process that started during the early Middle Ages and was highly functional as long as it occurred on a limited scale but became antifunctional as it pervaded the entire complementation system of these languages.