Over the past 10 years the CN Tower in Toronto, Canada (height 553 m above ground level), has provided an excellent opportunity to study the lightning characteristics of tall slender structures. In this work, the statistical relationships between the magnitude of the vertical electric field in the immediate vicinity of the tower and various parameters associated with actual lightning strikes to the tower are presented. These parameters include the flash duration, number of strokes per flash, and interstroke interval times as measured by a video recording sysem as well as the peak current amplitude, time to peak current, time to half-tail, total duration, and total charge of each stroke measured using a Rogowski coil. The results show that a significant number of lightning flashes strike to tower in the absence of large electric fields (fields less than 2 kV/m in magnitude). This implies that thunderclouds can be at a considerable distance from the tower during lightning strikes. These ''low electric field'' strikes are shown to have significantly different characteristics than those which occur during or just after periods of large electical field activity (large fluctuations and field strengths ≫2 kV/m) when thunderclouds were close to or directly above the tower. The data presented were collected over the time interval from 1978 to 1986. ¿ American Geophysical Union 1989