Sarah Dunning spent most of her twenties working for Deutsche Bank in London in a job she loved. But when her first son was born she decided she wanted to stay at home to look after him.

Over the next 18 years, Dunning, 47, had three more sons, moved countries twice, became a school governor and did a big house renovation. By the time her youngest child was in secondary school, she was feeling the itch to get back to professional life. The problem was, how?