Major junior

Junior hockey is ice hockey competition generally for players between 16 and 21 years of age. Junior hockey leagues in the United States and Canada are considered amateur (with some exceptions) and operate within regions of each country.

In Canada, the highest level is major junior, and is governed by the Canadian Hockey League, which itself has three constituent leagues: the Ontario Hockey League, Quebec Major Junior Hockey League and the Western Hockey League. The second tier is Junior A, governed nationally by the Canadian Junior Hockey League.

In the United States, the top level is Tier I, represented by the United States Hockey League. Tier II is represented by the North American Hockey League. There are several Tier III leagues throughout the country. A limited number of teams in the Canadian major junior leagues are also based in the United States.

In Europe, junior teams are often sponsored by professional teams, and act as development and feeder associations for those organizations.

In Canada, junior hockey is one level above minor hockey, the level of ice hockey played by youth (often called "youth hockey" in the United States, so as to not to be confused with minor league professional hockey).

Junior hockey in Canada is broken into several tiers, and players aged 16–20 at the beginning of the season are eligible. Hockey Canada is enacting rules designed to limit the number of 16-year-olds allowed to play junior hockey, preferring most remain at the midget level.

Major junior hockey is overseen by the Canadian Hockey League (CHL), which acts as the governing body for its three constituent leagues:

The CHL currently places a cap of three 20-year-old or overage players per team, while only four 16-year-olds are permitted. While fifteen-year-old players were formerly permitted to play a limited number of games per season at the CHL level, they are now permitted to play only if they are deemed exceptional by the CHL. Five players to date have qualified under this rule: centre John Tavares in 2005, defenceman Aaron Ekblad in 2011, centre Connor McDavid in 2012, defenceman Sean Day in 2013, and centre Joseph Veleno in 2015. CHL teams are currently permitted two "imports" (players from outside Canada or the US, generally from Europe or Russia) each, though this cap is expected to be reduced to one within a couple of seasons.

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