Directed cell migration is crucial for many cellular processes, including development, wound healing and tumour metastasis. Cell polarisation is controlled by guidance cues such as growth factors, which localise to the leading edge and activate receptor tyrosine kinases (RTKs), resulting in spatially restricted Rac activity. However, the exact way in which RTKs control the local activation of Rac remains unclear. On page 2285, María Martín-Bermudo and co-workers address this question in border cells (BCs) of the Drosophila egg chambers as a model system for guided cell migration. They identify the GTP exchange factor Vav as a key factor that controls the local activation of Rac. Vav proteins have been implicated in cell migration before, but it was unclear whether they have a regulatory role. The authors now show that BC migration is impaired in the absence of Vav, and that Vav is required for the stabilisation and maintenance of protrusions at the front of the BC cluster. They also find that upon activation of the PDGF- and VEGF-related Receptor (Pvr) with its ligand, Vav is phosphorylated and directly interacts with the intracellular domain of Pvr. Finally, they demonstrate that Vav is required for the asymmetric distribution of Rac activity in BCs. Taken together, these data suggest that Vav acts as a signal transducer that couples signalling downstream of guidance receptors to the local activation of Rac during guided cell migration.