All languages seem to have nouns and verbs, while the dimension of the class of adjectives varies considerably cross-linguistically. In some languages, verbs or, to a lesser extent, nouns take over the functions that adjectives fulfill in Indo-European languages. Like other such languages, Latin and the Romance languages have a rich category of adjectives, with a well-developed inventory of patterns of word formation that can be used to enrich it. There are about 100 patterns in Romance standard languages. The semantic categories expressed by adjectival derivation in Latin have remained remarkably stable in Romance, despite important changes at the level of single patterns. To some extent, this stability is certainly due to the profound process of relatinization that especially the Romance standard languages have undergone over the last 1,000 years; however, we may assume that it also reflects the cognitive importance of the semantic categories involved. Losses were mainly due to phonological attrition (Latin unstressed suffixes were generally doomed) and to the fact that many derived adjectives became nouns via ellipsis, thereby often reducing the stock of adjectives. At the same time, new adjectival patterns arose as a consequence of language contact and through semantic change, processes of noun–adjective conversion, and the transformation of evaluative suffixes into ethnic suffixes. Overall, the inventory of adjectival patterns of word formation is richer in present-day Romance languages than it was in Latin.