What is the general strategy behind the Queen's Gambit declined as white?  Specifically the semi-slav, and slav.

you know the semislav and slav is not a part of queens gambit?:) i think the main idea in slav is to have that known pawnformation with pawn at c6,d5 and e6, develop pieces and later open the game with the pawnpush e6e5 or c6c5 but i know nothing about the slav. i might be all wrong:)

• 1.d4 d5 2.c4 c5 Symmetrical Defense
• 1.d4 d5 2.c4 c6 Slav Defense
• 1.d4 d5 2.c4 Nc6 Chigorin Defense
• 1.d4 d5 2.c4 e5 Albin Countergambit
• 1.d4 d5 2.c4 Bf5 Baltic Defense
• 1.d4 d5 2.c4 Nf6 Marshall Defense

These variations are all considered part of the QGD.

Last time I checked 1.d4 d5 2. c4 e6 was the QGB, the others are, as you yourself just said, Slav, Chigorin defense etc.

1.d4 d5 2. c4 dxc4 isn't the QGD either.

d4 d5 c4 is the QG. dxc4 is the QGA, anything else is a variation of the QGD.

 They're part of the Queen's Gambit. But only 2...e6 is the Declined.

Anyways, the initial strategy of the QG is to put pressure on Black's d5 pawn (the threat is 1.d4 d5 2.c4 ... 3.cxd5 Qxd5 4.Nc3). Black has various ways to defend against this (that list of 2... variations).

From there White's strategy varies, there are many different plans, it depends on what Black does and on taste. Chess would be a poor game if there was only a single strategy after 1.d4 d5 2.c4 :-)

jdilley, the Slav, Semi-Slav, etc. are all declining the gambit by not playing 2... dxc4, but only 2... e6 gets called the "Queen's Gambit Declined."  It's just a weird nuance with the Queen's Gambit.  Are you asking about all of the different variations, or just the QGD proper?