PADI governs the certification of scuba divers and instructors worldwide to ensure consistent training standards. Prior to PADI's founding in 1966, scuba training was unregulated and often unsafe. PADI established uniform certification requirements for divers and instructors. Today, over 6,200 dive centers adhere to PADI standards and its 136,000 certified instructors have issued over 23 million certifications. PADI offers certifications for various diving skills as well as instructor levels like divemaster, which requires candidates to have rescue diver certification, medical clearance, and a minimum of 40 logged dives.