I do it fairly often.
You will most likely need new shorter doors. Other mods to the cabinet will really depend on the sink you choose and the width of your base cabinet. You will need to pull the front, then either install a taller front or just a plain panel cut to fit the sink.
You may need to build a platform to support the sink, or use a sink harness. ( I think Kowboy recommends the harness.I don't know much about those as I'm usually long gone by the time the sink is set).
If you can, try to go for the type of sink that overlaps the cabinets sink front, it's alot easier cutting the front out when you can count on the overlap covering the cut line.