Cell motility is a critical determinant of prostate cancer metastasis. The current review discusses the role for cell motility in metastatic dissemination, the evidence that prostate cancer metastasis is dependent on increased cell motility and describes the molecules whose expression has been shown to correlate with the increased motility that accompanies prostate cancer progression. These include receptors for growth factors and cytokines that regulate cell motility as well as intracellular proteins that interact with actin or that regulate signal transduction associated with cell motility. Motility related modulators include both positive regulators of cell movement that are upregulated during tumor progression and suppressors of cell movement that are down-regulated during progression. Because altered expression of such genes may determine the metastatic potential of any particular prostate tumor, we conclude that the appearance or disappearance of motility-related molecules could be used to aid in the diagnosis and prognosis of human prostate cancer.