Only if the the lesser side's king is trapped in a corner of the same color as his bishop. Here's an example.
White will play Rb3, forcing the bishop to move. It has to move so it can block at a6. Otherwise, Ra3 will be mate.
1. Rb3 Bc4 2. Ra3+ Ba6 3. Ra2 (anywhere) Zugswang! Ka8 4. Rxa6#
My endgame book (Fundamental Chess Endings by Muller and Lamprecht) has this to say:
A lone rook normally cannot win against a bishop, especially if the defending king is in a corner opposite to the bishop's colour.
As an example of a win, they give the following position (black to move):
This is won for white no matter where black's bishop is (as long as it's a dark square).
Finally, I found this, which may be useful:
http://www.anadune.com/chess/endgames/kr_kb.html