The Very Small Array (VSA) is a fourteen-element interferometer for sensitive measurement of the CMB anisotropies on scales of three degrees to ten arcminutes. The telescope is now observing on site in Tenerife after a period of commissioning, including the first map of the Sunyaev-Zel'dovich effect in the Coma cluster.

A distinguishing feature of the instrument is that each antenna in the array tracks quasi-independently, providing a characteristic fringe rate per baseline which can be used to reject many systematics. This effect has been optimised in the antenna array design.