The morphosyntax of negation in Berber is rich and complex, and appears to be the outcome of multiple processes that have taken place over different time-periods from prehistory to the present day. The most noteworthy issue is the tendency towards a redundant marking of negation, not only by means of discontinuous morphemes (circumfixes) but also through the use of special “negative verb stems” – a feature that is attested in nearly all of the Berber-speaking area, regardless of the type of negative affixes in use. In this paper, I attempt to single out the main processes that have led to the present stage, taking into account the etymologies of prefixal and suffixal negative morphemes, the origin of negative stems and the role of the so-called Jespersen’s cycle in the evolution of Berber negation.