Farnesyltransferase (FTase) is a major molecular target for the development of novel anticancer drugs that are designed to disrupt the aberrant signal transduction circuitry of tumor cells. The discovery more than a decade ago that farnesylation of Ras, one of the most prevalent oncoproteins in human cancers, is required for its cancer-causing activity was the initial stimulus to target FTase. However, it is now clear that yet to be identified farnesylated proteins other than Ras also play a pivotal role as targets for FTase inhibitors (FTIs). In this review, important mechanistic issues on the antiproliferative, pro-apoptotic and anti-angiogenic activities of FTIs, with an emphasis on potential FTI targets, will be discussed. Important clinical issues associated with translational aspects of hypotheses-driven clinical trials will also be discussed.