In November 2, 2010, for the first time in almost four decades, Californians will vote on an initiative that would legalize possession and cultivation of marijuana. Proposition 19, the Regulate, Control and Tax Cannabis Act of 2010, would make it legal for anyone 21 or older to possess, share, or transport up to an ounce of marijuana for personal use and to grow up to 25 square feet per residence or parcel. Cities and counties (but not the state government) would be authorized to regulate and tax commercial marijuana production and sales.