Opening, middlegame, or endgame? For me = the opening, because I don't understand yet the theory behind the opening.

The endgame is by far the hardest for me.

Middlegame... I crumple around that time...

the winning phase

lol, no duh...... opening and middle game for me

middlegame, so complex and the positional shuffling and tactical possibilities that arise usually are overlooked by me.

I absolutely stink in complex middlegame positions.

I'm proficient in the endgame and know to stay away from unfamiliar openings, but long combinations are hard for me.

The endgame is tough, but winning is sometimes tougher.

I personally need work on the late opening and middlegame, though my endgame isn't exactly good either.

endgame is the most difficult with middlegame a close second.

definatly the endgame,why? because most games are more or less over by the time you reach the endgame,so it,s a bit of a of a formality,barring blunders, which tend not to happen because there,s so little material left.

Opening, I'm an ending expert but not opening. I can handle it, but its hard to choose how to start because it affects your game.

If I don't play hypermodern I come out of the opening at least a pawn down.

The transition from the middle to the end - that's where I make most of my mistakes, and set myself up for a loss.

Unless you are master or close to it (USCF not 2200 here) you need to work on all phases of the game, if you are being serious about chess anyway.

Actually 2200 isn't the end of learning about the opening or middlegame or ending,

but I hope you get my point.

Endings, no doubt.

A lot of the time I have a hard time consolidating my gains, so I suppose middlegame. I just lost a tourney game on here where I was positionally better for the majority of the game, but I just couldn't play clean enough to not let the advantage dissapate. Very disappointing. It is an important skill for all to learn, how to convert strategic advantages to their physical counterpart.

Endgame. Openings are usually routine enough to find one's way to middlegame. Middlegame isn't easy, but it's usually tactical at some point and strong intuition steers one through. Endgame is subtle and some positions such as king + pawn(s) demand an extraordinary amount of calculation.

Endgames.

Great question...though the answers aren't going to help any of us :P

I walk a fine line with openings.  I understand there's a lot of tried and tested theory there, but I can't help but feel that that theory is a result of something deeper.  Some insight.  Some basic principles that are applied, but applied with flexibility.  So I don't subscribe to "book" playing, and...well...my opening game suffers as a result because I'm not a chess genius :)  But dammit, I'm going to keep trying until I attain the spirit of the opening rather than the rehashed theory of it.

Middle game...I swing like a pendulum between absolutely stunning insights and outright drooling stupidity.

Eng game.  Particularly those pawn/king endgame situations.  I abjectly suck.  I keep trying to see it, but I just can't.