Hi Andres.

Firstly, a PhD in business should not be considered an alternative to an MBA. I may be mistaken, but your decision to undertake a PhD instead of an MBA because of the cost of the latter degree suggests that you may have succumbed to this line of thinking. If so, you should be aware that the two degrees are designed for vastly different purposes. Generally speaking, an MBA is geared for a career in industry and emphasizes the enhancement of practical tools for managers and other professionals within the business community. A PhD prepares you as an academic research. It calls upon vastly different tools and a very different approach to business issues.

Now that's sorted, what an ad comm look for varies by each specific field. To give you a very broad idea, across all fields, apart from grades and test scores (your GMAT will probably need to be upped if you're targeting a tier 1 school), an arsenal of quantitative skills is generally required. The demands are higher in specializations like Finance and Operations Research (where you'll need lots of pure math) and less so in behavioural fields like Organizational Behaviour and CB Marketing (you'll still need a solid grounding). Beyond this, research experience is always useful; publications (in peer-reviewed journals) can be a huge bonus but at the very least an Honours thesis (preferably with some empirical work involved) or assisting a professor will send a positive signal to an ad comm.

Work experience may or may not be relevant depending on the area. I know that Harvard strongly prefers candidates with (quality) work experience for their OB degree. Depending on sub-specialization, I'm told that Accounting also favours experienced candidates.

Letters of recommendation are known to be gamebreakers. Get an outstanding reference from someone well-known in the field and you'll have a good chance anywhere. This is hard to come by though, so just make sure you have a few people you know who'll go to bat for you.

I can't say much more than this without knowing more about your background. However, you should understand that even those with the strongest credentials are often turned away from some programs. If you're truly keen on a PhD, home in on what interests you. Identify the field (you may have already done so but it wasn't clear from your original post) and proceed to subject. If you do enough homework, you'll probably even get an idea of the topics you could research. Then expand your search beyond just Harvard to other schools and professors working on the things you want to work on. Note what your profile lacks by looking at the CVs of current candidates and alumni. Try to address any deficiencies, then apply widely.

I'm in no way an authority but from what I've learned, I would say 50+ quant for business economics. You *could* get away with a slightly lower quant score for strategy if you have interesting work experience, a strong math background and if you indicate that you're interested in behavioural research. For both fields, at a minimum you should aim for a total score of around 730 to survive the initial screening.