user8291: As title above, what is the point or the main idea of a very early ...a6 Pawn move in Queen’s Gambit Declined? I see that the move is fairly popular at GM and even top level. 

user18809: It is hard to tell exactly without an exact line, but normally it has the idea of following with ...dxc4 (putting the enemy bishop on the c4 square), ...b5 (now kicking it away) and ...Bb7.
This solves the annoying problem of placing the c8 bishop on a decent square

8291: <p>As title above, what is the point or the main idea of a very early ...a6 Pawn move in Queen’s Gambit Declined? I see that the move is fairly popular at GM and even top level. </p>
 18809: <p>It is hard to tell exactly without an exact line, but normally it has the idea of following with ...dxc4 (putting the enemy bishop on the c4 square), ...b5 (now kicking it away) and ...Bb7.</p>

<p>This solves the annoying problem of placing the c8 bishop on a decent square</p>
