A physicist by training, Justin joined ICI in 1976 as a research scientist and moved from there into process development, operations, and then business management. His subsequent posts in ICI took him into marketing and business management in the UK and overseas, culminating in worldwide responsibility for ICI’s catalyst and technology licensing business.

In 1998, he joined the Environment Agency as NW Regional Director. He was responsible for all the activities of the Agency in North West England, and promoting enhanced partnership working across many local organisations.

Previously Justin was Deputy Chief Executive of the Health & Safety Executive where he was responsible for all of HSE’s operational work. He led and managed large, geographically dispersed teams of experts promoting improvements in health and safety, and led the HSE's response to major health and safety incidents across the UK