The IIHF rule book is used in both amateur and professional leagues worldwide.
US high school leagues use the National Federation of State High School Associations rule book, and varsity college hockey is governed by the National Collegiate Athletic Association's rules.
Hockey Canada and USA Hockey's rule books differ primarily in technical matters such as the severity of penalties handed out for various fouls.
The merits of this move toward a more standardized rule book, however, are debated in amateur hockey circles.
the low scores of NHL games have prompted the league to debate a wide variety of rule change proposals including enlarging the size of the goal, widening the blue and red lines to create a larger offensive zone, restricting where goaltenders can handle the puck, breaking ties with a penalty shot shootout, and eliminating the two-line pass rule.