Well first of all, you need to get a higher GMAT, if the PhD program requires GMAT scores. A 580 is too low, and you can do better I am sure. In order to further evaluate your chances, I need a LOT more information from you, as you can't encapsulate 11 years of work in five lines!!!!
I am missing a whole bunch of specific information to give you a more precise evaluation, and for that I'd suggest you fill out our form (which asks all the right questions) for a free consultation:http://admissionado.com/mba/free-consultation/
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