What are the risks involved with cave diving?

There are a number of risks associated with cave diving, risks that increase in severity as you move toward the exploration side of things.  However, there are risks no matter what type of cave diving you do.  These risks include running out or air, getting lost, equipment failure, and getting stuck.  Divers generally cannot surface right away and may have to swim a considerable distance before they can surface.  There may also be poor visibility and strong currents with which to contend.  While these are all valid risks, they can easily be minimized with the right safety precautions.  By carrying two or more extra tanks, using only 1/3 or your air going in and 1/3 going out, diving with one or more buddies, and running a line from the surface your chances of any of the above risks becoming reality are very low indeed.