Methods for modulating production of a T helper type 2 (Th2)-associated cytokine, in particular interleukin-4, by modulating the activity of a transcription factor, in particular the proto-oncoprotein c-Maf, that regulates expression of the Th2-associated cytokine gene are disclosed. Methods for modulating development of T helper type 1 (Th1) or T helper type 2 (Th2) subsets in a subject using agents that modulate transcription factor activity are also disclosed. The methods of the invention can further involve use of agents that modulate the activity of additional transcription factors that contribute to the regulation of Th1- or Th2-associated cytokines, such as a Nuclear Factor of Activated T cells (NF-AT) protein and/or an AP-1 family protein. Compositions for modulating Th2-associated cytokine production, recombinant expression vectors and host cells, as well as screening assays to identify agents that modulate c-Maf activity, are also disclosed.