Cryptococcus neoformans is an opportunistic fungal pathogen with a defined sexual cycle in which the α allele of the mating type locus is linked to virulence and haploid differentiation. Here we analysed a conserved MAP kinase cascade composed of mating‐type specific (Ste11α, Ste12α) and non‐specific (Ste7, Cpk1) elements. Gene disruption experiments demonstrate that this specialized MAP kinase pathway is required for both mating and cell type‐specific differentiation but not for virulence. The Ste11α, Ste7 and Cpk1 kinases were found to act as a co‐ordinate signalling module, whereas the Ste12α transcription factor functions with a redundant partner or in a branched or parallel signalling pathway. Our studies illustrate how MAP kinase cascades can be constructed from cell type‐specific and non‐specific components, yielding pathways that contribute to cell type‐specific patterns of signalling and differentiation.