The proposals which led to the 1948 Championship Tournament also specified the procedure by which challengers for the World Championship would be selected in a three-year cycle: countries affiliated to FIDE would send players to Zonal Tournaments (the number varied depending on how many good enough players each country had); the players who gained the top places in these would compete in an Interzonal Tournament (later split into two and then three tournaments as the number of countries and eligible players increased); the highest-placed players from the Interzonal would compete in the Candidates Tournament, along with whoever lost the previous title match and the second-placed competitor in the previous Candidates Tournament three years earlier; and the winner of the Candidates played a title match against the champion. Until 1962 inclusive the Candidates Tournament was a multi-cycle round-robin tournament – how and why it was changed are described below.