An analysis of measurements of electric, magnetic, and radiation field variations produced by rocket-triggered discharges in winter storms in Japan shows that a discharge initiated by a rocket with trailing and grounded wire is a negative leader that consists of continuous current and a pulse series associated with streamer development at the tip. The negative leader is not followed by a process analogous to a return stroke in cloud-to-ground flashes. Application of the electrostatic model of lightning as a bidirectional and uncharged leader in an ambient electric field to analysis of rocket-initiated discharges and positive cloud-to-ground flashes uncovers the commonality of processes occurring in both types of discharges. ¿ American Geophysical Union 1992