One of the most exciting aspects of recent research on cell-adhesion receptors is the realization that these molecules can participate in bidirectional signal-transduction processes. Integrins can convey signals from the extracellular matrix to the cell interior, and intracellular events can influence the affinity of integrins for their ligands. Another important emerging concept is that integrins and small GTPases of the Rho family work together to coordinate both cytoskeletal organization and signalling processes. In this review, the authors examine integrin signalling and integrin-GTPase interplay in the context of cancer cell growth and behaviour.