In basketball, an official (usually called a referee) enforces the rules and maintains order in the game. The title of official also applies to the scorers and timekeepers, as well as other personnel that have an active task in maintaining the game. Basketball is regarded as among the most difficult sports to officiate due to the speed of play, complexity of rules, the case-specific interpretations of rules, and the instantaneous decision required. There is one lead referee and one or two umpires, depending on whether there is a two- or three-person crew. In the NBA, the lead official is called the crew chief with one referee and one umpire. In FIBA-sanctioned play, two-person crews consist of a crew chief and an umpire, and three-person crews contain a crew chief and two umpires. Regardless, both classes of officials have equal rights to control almost all aspects of the game. In most cases, the lead official (in FIBA, the crew chief) performs the jump ball to begin the contest, though NFHS, NCAA, and the NBA, have allowed the referee to designate which official (referee or umpire; in the NBA: crew chief, referee, or umpire) shall perform the jump ball. Uniforms In American high school and college basketball, officials wear black-and-white-striped shirts with black side panels, black pants, and black shoes. Some state high school associations allow officials to wear grey shirts with black pin-stripes instead of black-and-white-striped shirts. NBA officials wear light grey shirts with black slacks and black shoes. The NBA shirt is light grey with thin white stripes, black sleeves, a black stripe on either side, a red and blue collar, the official's number in the center at the top on the back, and the NBA logo above the left breast and the Nike Swoosh on the right. NBA Summer League officials wear the same light grey shirt but with a black collar. The WNBA referee shirt is almost identical to the NBA referee shirt except that its collar is orange and the WNBA logo takes the place of the NBA logo. FIBA officials wear a grey (torso) and black (sleeves) shirt, black trousers, black socks, and black shoes. Officials in competitions organized by Euroleague Basketball – the EuroLeague and EuroCup – wear an orange shirt. Officials in the Israel Basketball Association wear the EuroLeague's orange shirt but sometimes wear royal blue shirts for contests between two Israeli teams. NBL