Queen's Pawn Game: Colle System
ECO D05
Move order
1. d4 Nf6 2. Nf3 e6 3. e3 b6 4. Bd3 Bb7 5. O-O c5 6. b3 Be7 7. Bb2 O-O 8. Nbd2 d5
Ideas
ECO D covers queen-pawn games and closed structures, including many Gambits and the Queen's Gambit complex. White builds a pawn center and keeps the position more closed than after 1. e4. This entry tracks a longer branch in the opening tree. Use the diagram and SAN list to recognize the tabiya, then try the line against Maia to explore typical plans in practice.