The talk will describe the activities in optical interferometry at JPL. The ground based activities center around the Palomar Testbed interferometer that began operating last year and the design efforts for the Keck Interferometer. The majority of the activities are directed towards SIM, the space interferometer mission, the successor to AIM the astrometric interferometer mission recommended by the Bachall committee in 1991. The talk will describe current efforts in these two areas.