The Queen's Gambit Declined is a chess opening which starts with 1.d4 d5 2.c4 e6. It is an old opening, and one of the most important. It is often used in top-class play. In this opening, called QGD for short, the struggle for the centre is the strategy of both players. Unlike the Queen's Gambit Accepted, Black keeps his pawn on d5 protected. A simple example: