Dedicator of cytokinesis protein 2 (Dock2) is a protein encoded in the human by the DOCK2 gene. Dock2 is a large (~180 kDa) protein involved in intracellular signalling networks. It is a member of the DOCK-A subfamily of the DOCK family of guanine nucleotide exchange factors (GEFs) which function as activators of small G-proteins. Dock2 specifically activates isoforms of the small G protein Rac.