Hilary initially lectured in law at Hull and Newcastle Universities before moving into private practice. She specialises in property development work for the NHS and other public bodies and private developers. She is recognised as an expert in this field for the North in Legal 500. She acts for many professional clients and in recent years has been instructed by local primary care trusts, GPs and developers in connection with the development of new surgery premises. She is a non-executive director of the Newcastle upon Tyne Hospitals NHS Trust and Vice Chairman of Three Rivers Housing Association.