A miniature aerosol collector based on electrostatic precipitation is described. The sampled aerosol is charged in the device by positive corona discharge and electrostatically collected. The device is operated as a collection interface for aerosol analysis, the collection surfaces can be washed in situ and the effluent subjected to chromatographic analysis on-line, all in a fully automated manner. At a sampling rate of 0.5 1 min - 1 , near unity collection efficiencies are obtained for aerosols of 1 μm and lower size, the size class of greatest environmental interest. Atmospheric aerosol constituents such as sulfate can be measured at the ng m - 3 level. The disadvantage of the present system is that some artifact nitrate is generated (due to NO x production in the corona) and reliable values of ambient nitrate aerosol cannot therefore be obtained.