Alternative splicing is now recognized as a ubiquitous mechanism for controlling gene expression in a tissue-specific manner. A growing body of work from the past few years has begun to also highlight the existence of networks of signal-responsive alternative splicing in a variety of cell types. While the mechanisms by which signal transduction pathways influence the splicing machinery are relatively poorly understood, a few themes have begun to emerge for how extracellular stimuli can be communicated to specific RNA-bindingproteins that control splice site selection by the spliceosome. This chapter describes our current understanding of signal-induced alternative splicing with an emphasis on these emerging themes and the likely directions for future research.