Whats a good opening when white plays d4?

I feel like I struggle a great deal when my opponent plays d4 in their opening. I am not sure why. I was curious about what particular openings are ideal for playing against white when they open with d4.

My favorite is KID, but it's a matter of taste. What have you tried that you haven't had sucess with?

a. The Queen's Pawn Game

b. Queen's Gambit

c. Slav Defence

d. Semi Slav

I usually start with the left hand (opening) and finish with the right hand (endgame). 

There are lots of good defenses against 1. d4 + 2. c4 from white.  It's really just a matter of finding one that you enjoy playing. 

Queen's Gambit Accepted
Queen's Gambit Declined
Slav
Semi-Slav
Chigorin (perhaps slightly dubious)
Albin Countergambit (perhaps slightly dubious)
Baltic Defense (perhaps slightly dubious)

Nimzo-Indian / Bogo-Indian / Queen's Indian
King's Indian
Grunfeld
Benoni / Benko Gambit

I'm probably forgetting some, too.

In retrospect now, looking back on the games where my opponent made that move, I lost more so due to blunders than anything else. I guess I primarily asked the question because I am starting to study opening theory a little bit, and I am starting to feel comfortable making moves against other openings, but I realized that I didn't really have a good idea of what specifically to do when white plays d4.

I'm really just starting to study and play chess in earnest, so sometimes it's nice to get a list of openings that tend to be effective and/useful against other ones. Its nice to get lists like these and then take a look on them in the opening explorer and then taking them on test runs in games.

Thanks for the ideas everyone.

another one that nobody metioned yet is dutch 1...f5, leningrad with g6 bg7 or stonewall with e6 and d5

yeah when youre starting out its going to be all blunders that lose for you and not anything with an opening. thats why players rec. to study double king pawn games 1.e4 e5 when youre starting out.. and for 1.d4 defense, the queens gambit declined.

Just checked your grade. When you start out using QP opening, you take a few hits. Choose one, perhaps the Slav... then learn the ideas behind it. Whats white's objective? Whats black's objective?   Once you know this, study a few master or top player's games and look out for the themes and continuations!

Thanks eaglex.  Like I said, I was pretty sure I was forgetting at least one. :)

Tarrasch too

Grob defense 1...g5 It's not as crazy as it sounds.. if your opponent is playing 1. d4 regularly then he might be used to closed positions and so slightly deficient in open tactical ability, which the Grob grossly encourages.

Its still pretty crazy though.

As someone who plays Queen's Gambit 80% of the time, I should say, I know what openings seem to be best defense against it.

Albin's countergambit is risky, but if you do it right and your opponent doesn't know how to fight it, they might fall into Lasker's trap. Unlikely, but check out the article on main page today, that had a discussion on Albin's countergambit and why it's actually good.

One other really good defense, is the one that goes into the Elephant trap, although not necessarily a 100% advantage for black, it still is a good position. I don't remember if it was Queen's Gambit Declined: Orthodox, or Tarrasch or something, but the Elephant trap seems to be a good way to defend.

With the queen's gambit your objective as black should be to secure your king, and develop. Secure your king against that white bishop + Queen diagonal attack that is common in Queen's gambit.

Going into too many "exchange variations" as black against their Queen's gambit, will probably not be 100% beneficial, but I have seen some players do it well.

I've seen one player who masterfully played Queen's Gambit Accepted--but this is rare, a lot of times, it seems when the player accepts Queen's Gambit, they lose.