Abstract
<jats:p>The term ‘lenition’ covers a broad class of sound changes, as does its reverse, fortition. There is no agreement on the very definition of these terms apart from the most general aspects, but some notion of consonant strength, a scalar property, is implied. The relevant category of strength may or may not be identical to sonority. Lenitions can also be understood in the context of the generally reductive character of language change, which itself follows from the overall architecture of language and its inherent variability. The delimitation of the phonological environments of lenition depends on one's definition of such processes. Intervocalic, especially post‐stress, positions are universally regarded as conducive to lenition; word‐final changes affecting consonants, however, present interesting problems and possibly conflicting interpretations. Different models of segmental phonological representation also have different implications regarding lenition and fortition phenomena. Models that apply unary features or elements are, in principle, able to capture strength relations as differences in the amount of structure that a segment has; consequently, they are also able to represent lenition and fortition processes as changes consistently leading to less or more structure, respectively.</jats:p>