Abstract: An electrostatic spray apparatus comprises a source of electrostatically charged liquid connected to an annular nozzle which discharges a hollow tube of electrostatically charged liquid, a source of atomizing air under pressure, an annular atomizing air discharge nozzle surrounding the liquid discharge nozzle, and an annular swirl chamber for the atomizing air. A plurality of apertures connect the source of air to the swirl chamber, the apertures being oriented at an angle to the radial direction to initiate a substantially tangential swirling flow of air in the chamber and being disposed to allow air to pass radially outwardly into the chamber. The chamber is defined by walls which tend to converge in an axial direction from the plurality of apertures towards the air discharge nozzle.