Results are presented from an intensive study of the stratospheric aerosol layer over Kingston, Jamaica, made in 1978–79, using a ruby lidar system. The aerosol layer is found to extend up to an altitude of about 35 km, with the layer maximum varying between 20 and 26 km. Comparison has been made of the principal layer characteristics with those obtained from other lidar and from direct measurements. Short-term fluctuations in the layer, occurring over a few hours or days, have been studied and are believed to be caused by the movement of irregularities in aerosol concentration. The long-term lidar record from 1965–79 is presented, showing the fluctuating volcanic influence during this period.