NSSF Supports IDPA Showing its support for a popular and growing segment of the shooting sports, NSSF has become a national premier sponsor of the International Defensive Pistol Association (IDPA). IDPA—the governing body of the shooting sport that simulates self-defense scenarios and real-life encounters—has been attracting thousands of new and experienced shooters since its formation in 1996. The organization’s membership has grown to more than 11,000, including members in 19 foreign countries. NSSF presented a check for its sponsorship to IDPA on Thursday at SHOT Show.