Behind the camera
- 1995DazzleWriter2 ep.
- 1985Christopher ColumbusScreenplay, Writer4 ep.
- 1984Murder, She WroteWriter10 ep.
- 1981Code RedWriter1 ep.
- 1977Seventh AvenueWriter3 ep.
- 1973The MagicianWriter2 ep.
- 1969Hawaii Five-OWriter1 ep.
- 1968LancerWriter2 ep.
- 1967MannixWriter1 ep.
- 1967The InvadersWriter4 ep.
- 1966Mission: ImpossibleTeleplay, Writer21 ep.
- 1951Schlitz Playhouse of StarsWriters' Assistant1 ep.
Also known as: Leonard Haideman · Leonard Heideman · Leonard Heiderman · Leonard Heidman · Leonard Herdeman · John Truman