Lately I've really been trying to improve my game, studying heaps and playing far more often, and I've found a huge hole in my play. I suck against 1.d4. I spent wayyyyy too much time studying white play and response to 1.e4, and as such neglected 1.d4. Now when I see it, I freeze up and can't decide how to respond.

As a Sicilian player I've tried my hand at the Dutch once or twice, but it doesn't seem to work out for me (although I admit that I haven't put much study into it). ... d5 works out, but I only seem to play solidly if white plays the Queen's Gambit, where I can decline and get into a familiar, comfortable position.

So my question to you is, how do you prefer to respond to 1.d4?

Try types of Indian. e.g:

@ kevinjin

In the King's Indian, after 3 e4, Nxe4 and black is winning. White plays 3 Nc3 first. This is the King's Indian:

queens indian is good but i also like the dutch defence now

after reading the first post the very basic ideas of the dutch is to grab space set up a fortress then smash through with e pawn

also being familiar with sicillian you might actually consider semi slav

sorry messed up move order

Also available is 

Grünfeld Defense

Last is Transposing into French (personal favorite)

there is no point throwing any opening out there

Thanks for the ideas guys, all of them were really helpful. I've played with the KID a little before (albeit against 1.e4 [no idea if that was the right idea, I didn't know what opening theory was when I was playing the KID back then]) so I'm kind of familiar with the system of it and I'm comfortable with the game that comes from it, so I think I'll go with that. I might give the Grunfeld and possibly the semi-slav a shot also, they look like they could bring out some new situations I'm not used to (which hopefully will improve my repertoire and all-round game). Thanks again, I really appreciate it :)

I agree; d5 blocks the d4 pawn, so it's probably the best thing to do.

   IM Stefan Buecker developed a system a few years ago called "The Vulture" It was very interesting and quite playable. It went 1.d4 Nf6 2.c4 c5 3.d5 Ne4!? The idea is if the Knight is eventually kicked by f2-f3 then it can go to d6 where it will eye c4 and participate in a eventual break at b5. Also by being at e4 it puts pressure on d2 and c3 if Black should opt for ...Qa5 at some point. I would recommend buying the book if it is still in print. Another very interesting and good defense to 1.d4 is the Dzindzi Indian defense, developed by GM Roman Dzindzichashvili. 1.d4 g6 2.c4 Bg7 3.Nc3!? Bxc3!? 4.bxc3 f5! If you look this opening up in a major database you will se that Black has very good success with it, almost to the point that White will often try to avoid it playing by 3.Nf3! Everyone also forgot the Budapest Gambit: 1.d4 Nf6 2.c4 e5!? 3.dxe5 Ng4. This opening can lead to very tactical and interesting play. Chess, after all should be fun to play!

How About the BENKO GAMBIT!!

My friend just started to play d4 on me and like you i was not very used to 1. d4. Then I learned that the benko gambit is one of the most well respected gambits and it is for aggresive players.

This is the Ideal setup

This is all i know about the benko gambit and I have beaten my friend a few times with it

I like the Dutch Defence Leningrad Variation--suits my style since I like playing for a win as black and using sharp non- gambit openings vs d4. But I also include the solid Nimzo depending on tournament standings. (Playing for a win when I don't really need to is meh to me...too much effort lol)

 how do you deal with an early e4 there are lots of tricks to deal with it

There are lot and lots of ways to respond to d4. I used to do Queen's Gambit Declined, just because that was just my natural response, but I do not know too much of it.

Currently I am responding with King's Indian Defence, as others have posted. I haven't looked too much in detail with it but I have watched quite a few videos on youtube from Kingscrusher and he likes to play it.

But I believe that if you do take this step, you would have to look into it quite a bit, as there are many deviations your opponent can take. Even very high rated players still use this response yet I feel like it's even better for us lower leveled ones as we do not necessarily know too much about every line and it allows us to be creative and it can also become very instructive.  

Def. the Budapest Gambit. Most class players haven't seen it, and it works well for 1. e4 players.

I used to have the same gut-wrenching feeling when my opponent started off with 1. d4. I always managed to get myself into awkward positions, with my pieces badly coordinated, bishops hemmed in by my own pawns, and a feeling not unlike one gets when in a full elevator. I tell you, it was awful!

Then I learned Benko's gambit. It starts of like this:

1. d4 Nf6

2. c4 c5

3. d5 b5

4. cxb5 a6

Black can achieve a lot of queenside pressure if white fully accepts the gambit.

I would definitely go with 1. d4 c5. It is a clever opening that if used properly can take away white's center control. Try it.

I like playing the Nimzo Indian, but other more 'dangerous' openings like the benko and KID are nothing to sneeze at

I stick to the Classical Dutch these days, which has the added bonus of working against 1. c4, 1. Nf3, and just about any other first moves besides 1. e4 and 1. g4.