Global Positioning System (GPS) observations between 1994 and 2000 at twenty-two sites in the Lesser Antilles and northern South-America indicate that the Caribbean plate, along its southern boundary, slips at a rate of 20.5¿2 mm/a with an azimuth of N84¿¿2 ¿E at 65 ¿W, relative to the South-American plate. East of 68 ¿W, 80% of the dextral slip is contained within a 80-km wide shear zone centered on the El Pilar-San Sebasti¿n fault system. West of 68 ¿W the plate boundary broadens to more than 300 km with dextral shear shared between the northeast trending Bocon¿ fault (9--11 mm/a) in western Venezuelan, and an offshore system near the northern coast. ¿ 2001 American Geophysical Union