Measurements of radiation from lightning at 2200 MHz have been made using a high gain, 1.4¿ beamwidth, parabolic antenna. For discharges to ground, radiation was observed to occur: (1) as a burst of impulsive activity during preliminary breakdown preceding the initial return stroke, (2) in conjunction with the initial return stroke, and (3) during the dart leaders of subsequent strokes. The latter two are similar to previous observations made at lower frequencies. The burst of 2200 MHz radiation during the preliminary breakdown generally occurred several tens of milliseconds prior to the first return stroke and lasted from 5 to 10 ms. We interpret the burst to be caused by breakdown passing through or near the main beam of the antenna.