From the website:
Since 1944, the Sports Car Club of America has championed one mission To bring motorsports to the masses of American men and women who are passionate about automobiles, speed and competition. From National Championships to regional events, whether professional or amateur, the SCCA exists to organize, support and develop auto racing at every level and provide an outlet for you to get out of the armchair and into the action. So, whether your passion is autocrossing, rallying or road racing as a professional or as a weekend warrior, SCCA wants to help you fuel your passion.