I fell into working in the City because I was good at maths. I started as an office junior in a boutique asset management company for emerging markets. Within three years I was a trainee fund manager at Aberdeen Asset Management. I built my career as an investments manager, but after a few years I started to become disillusioned - it was the time of the technology bubble bursting and a lot of companies were going bust, similar to what's happening now.

I didn't want to leave the City because I had invested a lot of hard work in it, and so I did some voluntary development work in Africa and then went back to help to set up a hedge fund business. After 15 months it became apparent that it was the wrong decision. I was working really long hours and was burnt out. There was a value conflict between my job and myself - whether you are a hedge fund manager or an investment banker, you are there to make money.

I needed more than that. Within a week I had sold my flat, moved out of London and given up my job.

The first thing you realise when you leave the City is that you have to adjust your lifestyle and manage your finances. That can come as a shock. I went to Australia, did an MBA and taught business English. I was determined to move into the charity sector. I believed I had knowledge I could share: commercial acumen, speaking the language of corporates, a strategic outlook. So I went into fundraising and worked for two charities, Enterprise Education Trust and Hope and Homes for Children.

It didn't work. I didn't have to work long hours, but it was a huge change. Culturally, the City and the charity sector are two ends of a pendulum swing. I wasn't challenged; the level of expectation placed on me was very low. I was quite frustrated. I realised that I had thrived in the City and missed the “work hard, play hard” environment when I left. In hindsight, I pitched myself wrongly and should have looked for something more strategic.

I moved back into the City to work as a training manager for a large financial services company. Now I design strategic programmes - regulatory or technical - and deliver some of the training myself. I didn't fall into financial services this time, it was an active decision, and I enjoy a more educational role. I've changed as a person and view the City as a very different place now.

I would not discourage anyone from going into the charity sector, but I would say: ‘Do your research.' You have to look at what motivates you in terms of work and your organisation. I don't regret working for charity. I have been a trustee and I give financially. I wouldn't rule out going back.

Times Recommends

• Gazprom brands Ukraine 'a barbarian' in gas row
• Services sector raises fears over UK jobless
• Retailers surge as profits survive sales plunge