Since its introduction, the game of indoor bowls has grown in popularity to the extent where it rivals some of the longer established sports. In 1938 there were about 150 indoor bowling clubs catering for a handful of enthusiasts. Eleven years later, when the Federation was formed, there were only 1,854 registered members. By 1962 there were nearly 2,000 clubs, having a total membership of over 66,000. This recent upsurge of public interest is due largely to the formation of the New Zealand Indoor Bowls Federation (Inc.), and the consequent adoption of uniform playing rules.