I have floresscent lights that flicker when other people have their lights on. When there are only my lights or 1 or 2 other lights on they work fine. Any suggestions as to how to keep them from flicker when there are other lights on. They are plugged into a screw in light socket up on the ceiling.

Sounds like voltage drop. How many watts are being used.

Please provide us with a better description of the failure. For example, when you say other people have lights on and your fluorescents flicker, do you other people within your home or do you mean neighbors in adjacent homes.

The first place to start is the branch-circuit for the failing lights. What else is on this circuit?

If the existing load on the circuit is to high, then the Ballast for the lights may not be able to pull as much start-up amperage as they need.