The method of awarding a bonus includes executing a game so as to define a combination (Step S2); ascertaining if the combination falls within a predefined sub-set of combinations (Step S3), and, if so, setting the combination as a target combination (Step S4). Once a target combination has been set, further games are executed (Step S5), each of which defines a further combination. If the further combination bears a predefined relationship to the target combination (Step S6) then bonus is awarded (Step S7).