Ever thought of throwing it all in to become an academic? Ex-Citigroup managing director Pete Hahn says going back to school need not be so frightening.

At the ripe old age of 47, I had spent half a career in banking, with the last two years on Citigroup’s London Operating Committee (mostly discussing staff reductions) as the bank’s senior corporate finance officer. Then Citigroup decided it didn’t need a senior corporate finance officer anymore.

Despite Citi’s ruthless reputation, I was given no time limit to “find something else in the bank”. I couldn’t – or didn’t – and chose to start a new academic career at City University’s Cass Business School, where I am now the FME fellow in the Faculty of Finance, expecting to complete my PhD in Corporate Finance and Governance shortly.

It was not an easy transition and I couldn’t find any precedent. It seemed academics from almost everywhere were downright hostile to giving me the opportunity and many of my former FTSE 100 clients couldn’t believe that I’d waste my time so. It has been an unimaginable struggle to catch up with 30 years of financial theory and blend it with my experience, but the rewards now look worth it.

Changing careers is no easy decision and retirement was not an option. Surveying my peers, I found many had goals of retiring at 50-55 and then doing some “non-executive director type stuff”. Thinking about living another 30-40 years, I wondered “how can you spend 30 years staying on the top of your game and then spend the next 30 years with the ‘new knowledge’ part of your brain turned off, recounting an ever distant and dated experience… you might stay physically fit, but your brain and value will rot pretty quickly.” For me, I knew that I had to find a career with upside – knowledge upside most of all.

Earlier on I had wanted to become a business academic, but couldn’t rationalise the opportunity costs. Now I can accept these and, even better, I have a lot more experience to add to the theory that underpins business.

The decision done, the execution was frightening. I checked out the major local business schools and economics centres, assessing each in order of distance from my home – bankers know that only foolish clients make decisions on league tables!

I found out that business schools have two classes of faculty. The ruling class is still determined by publication in academic journals and the second class is made up of ‘clinicians’, ‘practitioners’, and – seemingly the lowest of the low – ‘teachers’. Before figuring out this class structure, one London business academic told me that I could probably be a good clinician and teacher!

When I explained that I was interested in a PhD, the responses were almost heated. The first school said (1) we don’t like PhD students over 30, (2) we don’t like students with business experience and (3) most of our PhD students come without prior business studies – this is a business school, remember. Finally, recommending I consider something like a PhD in mythology instead, they suggested that I not apply. Other schools weren’t much better, adding that “business people can’t write” – and this wasn’t about academic-style writing. The majority of academics I wrote to didn’t even reply!

Fortunately, early on I met one of London’s top finance academics, Cass Business School’s Professor Mez Lasfer. He saw me as a unique student and thought that my experience might lead to some very different interpretations of business data than those provided by traditional academics. John Plender of the Financial Times also encouraged me to take the leap, insisting that academia had plenty of room for a few people with the City’s reality experience.

For those of you considering this career path, be warned: a PhD is a lonely, time consuming, expensive, and often boring undertaking. But if you’re interested in your subject, the downsides disappear quickly. I am regularly approached by major newspapers, websites, radio and TV and pension forums. Masters students also appreciate the experience tied to the learning and theory.

I have been approached by fund managers who value someone with in-depth experience in corporate finance – plus quite a bit in tax, accounting, capital markets and corporate governance. I’ve also been approached by search firms looking for non-executive directors with financial market depth and credibility. So, if you feel there is some bit of academic or intellectual hiding inside you, academia might just be a worthwhile slog.

There’s also a non-monetary pay-off. My long hours are flexible and I enjoy walking my children to school each morning and discussing their homework with them on the way home – two benefits that are worth more than even cash bonuses and are also extraordinarily time sensitive. My advice to anyone thinking of making this kind of decision is therefore simple – don’t leave it too late.

· Pete Hahn was awarded a fellowship from the Foundation for Management Education (FME) in April 2007. He expects to complete his PhD later this year at London’s Cass Business School. Prior to joining Cass, Pete was a managing director at Citigroup in London where he was also their senior corporate finance officer for the UK.

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