Am I too old for business school?

Age is not an intrinsic handicap per se, however it does mean that you have to take special care in addressing a few key issues. These are the questions to come to mind (in no particular order of importance),

1. Timing.
Why now? Why not earlier like most b-school applicants? Or why not a little later and do an E-MBA? Chicago is famous for emphasizing this point, but I think most top b-schools will also be very interested to know your rationale for applying.

You are at an age where it's a little on the old side for an MBA, and perhaps a little too young/inexperienced for an E-MBA, so I think it's even more important to explain clearly why you feel you have to get an MBA right now.

2. Future plans.

Applicants to good b-schools tend to have pretty good jobs and/or are on track to be quite successful at what they currently do. Hence, one of the biggest question that all applicants (and not just older ones) have to answer well is why an MBA is needed. I feel this is more so with older applicants because they tend to be more well-established in their career, so the need for an MBA is less obvious.

This is even more critical when you are trying to switch careers. For example, if you have been an engineers for 10+ years, and now you want to become and I-banker, you must have a very compelling reason for this. Also, I think there are two kinds of career switchers, 1) the "engineer to i-banker" career switcher, which is basically going from apples to oranges and 2) the same/related field but a different role career switcher, e.g. you were an engineer, but you hope to lead an engineering team post-MBA. I get the feeling you belong in the latter group (so do I actually,) and I think you will be able to give a very compelling reason for your application.

I also feel this is important because this will definitely affect how the AdCom views your chances of getting a good job post-MBA. Again to re-use my earlier example, if you're an engineer with 10+ years of experience but want go into the banking industry post-MBA, this will be quite challenging. And even if you do get into banking, because of your inexperience in that area, your compensation might not be as competitive as some of your peers. So if you're a complete career switcher (i.e. going from apples to oranges,) you need to show why you feel this switch is necessary this late in life. Otherwise you come off as someone who just wants to go to b-school because you're not happy with status quo. Always remember to come off as the guy going from one green pasture to a greener one, and not as the guy who's fleeing a forest fire.

3. Fit
There is no secret that (most) b-schools are trending younger, and the average age in (almost?) all b-schools are south of the 30 line. So you will be interacting with people significantly younger than you when you get into b-school. I think you have to show that you will be able to fit in well and be young at heart at least. This doesn't mean being to drink the younger students under the table, and stay out as late as them and party. It does mean being able to work with them as a peer, understand the (slight) generation gap, and being very open-minded. It's one thing to show you can manage younger people (which as an older applicant, you should not have any problems with), but it is another to show that you can work with younger people as peers.

I am an older applicant as well (32 at matriculation) and these were some of the issues I gave a lot of though to and tried to address to the best of my ability in my applications. Hope they can be some help to you as well.