What concerns you about driving ? Have there been any reliable studies on the affects of marijuana while driving ? Does marijuana impair motor skills ?Once "all the ducks are in a row" probably time to legalize it, as long as it is strictly regulated and all laws pertaining to it are enforced. Education on the effects of it to young users (under 25 is important) but they have to learn to take some responsibility. For me personally my biggest concern is the driving aspect. Are there reliable tests in place so impairment can be properly measured and stand up in court?