Alright, so Homer and I have been trying to get nice and collected. We've failed miserably, but this morning I had revelation as to why it wasn't working.

 Balance.

We've got impulsion,, suppleness.  I realized that I'm being used as a tool to balance my horse, and I've also realized my aids don't feel very effective.

 This is especially evident in the canter when he leans into circles drastically. I can hardly keep him out in a circle at this point. This leads me to believe that my steering is down too, but could that just be a balance issue?

 Anyways, I'm wondering what I need to start working on to fix this.
 

I haven't seen you on here in a while!  Constant correction is going to be needed until he builds the strength to stay balanced on his own.  When you're trotting around, does he drift to the left or right?  You will need to use your leg aids to keep him straightened out every stride. Eventually, you won't have to do so much correcting.  Having good control over your horse's shoulders will really help to create balance and straightness.

Also, make sure he is balanced in the trot before asking for the canter and you will get a much better response.  Some exercises that I used with Rizzie to improve her canter depart and therefore her canter in general are these:

Ask for canter on a change of direction.  Trot a 20m circle or figure eight.  When you have steady rhythm and a forward pace, make as small a circle (with the intent of changing direction) as you can while really using your outside aids to push his shoulder over... then when you go to actually change directions, LOOK LEFT, STEP LEFT, CANTER.  Or to the right if its the other direction.  It may take a few tries, but if he doesnt canter right away, insist that he does and then stop right away and try again.  But make sure you are really getting hiim to hold his shoulder with your outside aids when you do that small circle... it will be easy for him to depart when you ask correctly.  When he departs correctly and instantly, let him canter around a few times so he knows he did the right thing. 

Another exercise would be to make a figure eight while staying on the same bend the entire figure.  So, you will be doing a counterbent circle and a correctly bent circle.  When you have steady rhythm, a good pace, and he is listening to your aids.. you can ask for the canter in the same manner as before at the change frmo counterbent to correctly bent.  So you're going around counterbent... you come to the middle of the figure and you LOOK, STEP, CANTER. 

Acheiving a balanced depart is the most important part of canter work.  It will be much easier for him to stay balanced from a balanced depart than it will be for him to balance himself from a sloppy depart.  He may only be able to stay balanced one or two circles at first, but with time and practice he will gain strength.  To improve balance further once you've gotten into the canter correctly, doing counterbent canter and leg yielding in and out on a circle will help him lift his shoulders and stay balanced rather than leaning and running.

 Hope that made some sort of sense and will help a little.  Good luck!

Oh and if its collection you're looking for, you're going to want to make sure you have a nice, balanced FORWARD working canter before you start asking for collection.  You don't want to lose that forward momentum by asking for collection too fast, too soon.  It would be incorrect collection, because even in a collected canter, the impulsion and forward motion are still there.  Making sure your horse is upright and not leaning in the canter will help when you ask for collected canter.  Counterbent canter is a great exercise for this.

Nicole has written good exercises to try out. But are riding him from inside leg to the outside rein? I find that this happens when I use the inside rein too much to bend the horse. You want to control the shoulders of the horse and bring them into a bend. This means using the outside rein. That way he'll be much more maneuverable. Also, when riding on a circle, keep your inside shoulder back (I've been working on this too-I tend to keep my shoulders straight and just turn my head to see where I'm going) and try to sit in the middle of the saddle as the movement sometimes puts riders way to the inside. And to compensate this, the horse spirals in. Also, if this is a strength issue - try keeping the canter sessions short and circles large until your horse develops enough muscles to carry himself and you properly.

Hope this helps, good luck!

He tends to be loosy at the canter, something I hadn't noticed until very recently. So, I think it's probably a balance issue judging by the way he takes curves. With no rein contact at all he leans in too, but I will try a little more outside rein- then I feel as though he's leaning on me, though.

I should mention he's not being ridden regularly by anyone but a beginner rider at this point. It'll be about another month before he will be ridden by me on almost a daily basis. 

I will try the excersises recommended when I can, thank you =)

  Wow, that sounds quite a bit like the problem I have been having with my big guy.  I took him to our Dressage lesson yesterday and finally had the "oh you mean I need to do this" moment.  My trainer had me do this:

  Start on a 20 meter circle at the walk, when your horse is supple, forward and balanced then ask for the trot.  At the trot you want the same thing, make sure he is soft before you event think about the canter.  While you are trotting (?) spiral out until you feel him take a light contact on the outside rein, use your outside leg to keep him straight and the inside to keep the bend.  Once he is soft ask for the canter, again spiral out slowly, don't spiral in.  I think it took half the circle for my guy to understand that I was trying to help him balance and get his hind end under him to have a nice round canter.  Once he gets light and obedient, don't slam on the brakes, continue to spiral out slightly in the circle and slowly, squeeze and release (half halt basically) for the trot....Do the same thing (spiral out) down to a walk, change directions and repeat. 

  My guy has never had a great canter, the movement is there but after riding yesterday it dawned on my trainer and I that my ring at home is a little bit more narrow than the standard dressage ring, well he's just too big and not balanced enough yet to hold the canter in that arena.  At her place he was much softer, more balanced and didn't *surge* or bolt like he does at home.  Now at home, I was told to do this exercise before I jump or even out on a trail ride where there is plenty of room for big circles.  Hope this helps!

 Hi

I have been working with a coach so I will tell you what she tells me all the time.  Inside leg to outside rein and make sure your inside shoulder is up and back.  His shoulders are your shoulders.  If he is dropping his shoulder to the inside correct by lifting the inside rein and giving more inside leg.  I was having a problem with the inside leg and could not give anymore so now I have decided to use spurs for a short time to get her listening more effectively to my legs.  Just a word of caution about the spurs though.  When you do spur make it a short direct spur instead of constantly doing small jabs.  Horses just find that annoying!!  Get the point across by being very direct.  Also, what kind of saddle are you using?  Does your saddle put you in the right position easily?  If he is a new horse to you and you are using a new saddle you may want to get that checked out with a trainer.  Another issue as well to look for, make sure you are sitting squarely in the saddle and that when you ask him to circle that you are not leaning into the circle as well.  Well, have fun with it and don't give up hope.  It is always a work in progress and that is what makes it interesting and challenging!!! 

if you follow the scale of training. Rhythm, Looseness, Contact and acceptance of the bit, impulsion, straightness, and collection. if you follow this balance will fall in naturaly in place, especially if you have good rhythm.

 If he falls in you also have a contact issue, he needs to respect and accept a half halt. if you half halt he should lift his shoulders and sit more.

 half halt to make him get off his shoulder.