Communication is an essential part of Bridge. It starts from the very first call by the Dealer to the last few cards played by the Declarer. During the bidding, you and your partner communicate via the symbolic meta-language of Bridge. You make use of standard -and sometimes not so standard- protocols and hope to arrive at the optimum contract with your particular cards.
        The bidding is over and the Declarer is playing the hand. Here communication between the Declarer's hand the cards on the table is crucial; a connective link or Entries must be maintained. If not (and you might have 
experienced this), you could have beautiful winning tricks in the Dummy, but no way to get there. No Entries! Very frustrating. And all because you did not consider the transportation problems between the two hands. Of course there might have been times when there was little or no connective links between the hands; or perhaps some sharp defenders had cut these links. But even then, there are ways to maximize your communicative skills. 
        The first step is to recognize Entries. If you do not know what they look like, you may never make use of them at the appropriate moment. Once you see the Entries you must know how to preserve them, even when they are attacked by astute Defenders. But what if there are no Entries? Then the problem is how can you create them? 
        Winning tricks, taking finesses, establishing winners, discarding losers, ruffing, cross ruffing, dummy reversal, throw-ins, squeezes, trump coups, etc. are all weapons in the Declarer's arsenal. But in order to use these weapons, the transportation lines must be open. There must be Entries. Four general Entry strategies that will be considered are:
 1. Unblocking.
 2. Overtaking.
 3. Use of trump.
 4. The Duck. (No relation to Donald.)