Which Is Better - A One Year Or A Two Year MBA Course?

To answer this question let us consider the case of an aspiring applicant that I recently met. This young man already has an MBA degree (acquired in 2008)  from a leading international management institute. However, he feels he still has more to learn. 

Moreover,  his experience of working with one of the Big 4 auditing firms in India had also turned out to be far from satisfactory.  Now he is keen to apply to other schools in the US and enhance his qualifications. He had worked for three years before deciding to enroll for this one-year MBA and it had not worked for him at all.