This chapter will outline novel treatment strategies predicated on the modulation of growth factor or cytokine-mediated signal transduction pathways. Several excellent recent monographs have addressed this tissue from the point of view of inhibitors of individual pathway constituents (1,2).The current focus will be on defining the pathways potentially relevant to the common neoplasms, followed by a consideration of approaches to modulating processes common to the action of various pathways, with mention of individual agents as they exemplify these strategies. In addition, opportunities for interdigitation of “growth-factor directed” and “traditional” therapeutic agents will be considered.