This is called the "diamond" series because playing the hand is considered best learned after learning basic bidding. The bidding book is, appropriately, the "club" series. (For those curious about the inevitable, defense is the topic of the "heart" series.) This is totally wrong, IMO. First you learn to play the hand, then you get wound up in the intricacies of bidding, which doesn't make any sense without understanding the essentials of how tricks are taken and hands are won. It would be like teaching kids football by starting with the kicking game. ( )