In this article we explore the issue of domain-specificity in language learning. the point to be argued here is that although language acquisition requires substantial domainintensive knowledge, some of the mechanisms used in concept acquisition can be seen as special cases of more general learning strategies; that is, domain-independent strategies operating within domain-dependent constraints. We present a computational model of concept 2cquisition making use of these strategies, operating within a model of lexical organization, called Constraint Semantics. This is a rich lexical semantics embedded within a “markedness theory,” constraining how semantic functions relate to one another. Constraint semantics is a restrictive calculus limiting the search space of possible word meanings for the language leaner. This, in effect, acts as a set of wellformedness conditions, defining the constraints for what possible logical decompositions a word might contain. the general approach taken here is based on the supposition that predicates from the perceptual domain are the primitives for more abstract relations. We then describe an implementation of this model, TULLY, which mirrors the stages of lexical acquisition for children. Examples are given showing how hierarchical structure for concepts is acquired, as well as the development of polysemy relations for verbs.