The focus of this paper is on the semantics of the Croatian prefix ‘do-’, or, more specifically, on its contribution to the verbal semantics and the resulting network of senses realized by all the ‘do-’ prefixed verbs in standard Croatian. Following a brief review of the current most influential theoretical treatments of the semantics of the Croatian ‘do-’, which is complemented by a brief review of the analyses of ‘do-’ in Polish and Russian, the central portion of the paper is represented by a detailed and systematic analysis and of the semantic components but also syntactic requirements of all the ‘do-’ prefixed Croatian verbs. In the conclusive part of the paper the authors propose a semantic network accommodating all the senses expressed by Croatian ‘do-’ prefixed verbs, which is interestingly paralleled by systematic syntactic requirements of ‘do-’ prefixed verbs falling into different semantic subcategories.