The Calder Memorial Trophy is an annual award given "to the player selected as the most proficient in his first year of competition in the National Hockey League (NHL)."

The voting is conducted by members of the Professional Hockey Writers' Association at the conclusion of each regular season to determine the winner.

[2] The last requirement was implemented in 1979 to block Wayne Gretzky (who had played a single season in the World Hockey Association the year before) from winning the award.

[3] After the Calder win of 31-year-old Sergei Makarov in 1991 (following the influx of Eastern Bloc players after the fall of the Soviet Union), the rules were further amended to require that winners be 26 years of age or younger.

Although Rookie of the Year honors were handed out beginning in 1932–33, the Calder Trophy was first presented at the conclusion of the 1936–37 NHL season.