Notable amendments to the rules include:

1866 – Forward passes are permitted, as long as there are three defending players between the receiver and the goal. This was the first step from a consideration of offside as seen in modern rugby towards the offside rule known in association football today. The fair catch (still seen in other football codes) is eliminated.
1871 – Introduction of the specific position of goalkeeper.
1877 – Full unity with the Sheffield Rules is established – several features of the northern code had been incorporated into the London-based association rulebook over the preceding 14 years.
1891 – The penalty kick is introduced.
1925 – The offside rule is reduced from three to two defending players between the player and the opponent's goal line.
1958 – Introduction of substitutes.
1970 – Introduction of red and yellow cards.
1992 – Introduction of the back-pass rule.
2012 – Goal-line technology permitted (but not required); first used in competition at the 2012 FIFA Club World Cup.