Alan joined the NHS as a porter in 1978, and then completed Registered Nurse Adult and Registered Nurse Mental Health training before joining the British Army as a Nursing Officer in 1987.  During his military career he reached the rank of Colonel and his appointments included: Manager of Military Departments of Community Mental Health, the MoD Nurse Consultant in MMH and the MOD Nursing Advisor in MMH. Alan was Senior Military Nurse and Commanding Officer at the Royal Centre for Defence Medicine during the peak of the Iraq and Afghanistan campaigns. His final appointment was as the first MoD Professor of Nursing. He completed operational tours in Iraq, Afghanistan, Balkans, Northern Ireland and South Africa. Alan has experience leading military and veterans specific research. His results are disseminated through multiple peer review publications. 

Since commencing at the University of Chester in 2016, Alan has been appointed as the principal investigator for over 35 research projects totalling over £8M; including awards from the NHS, Armed Forces Covenant Fund Trust (AFCFT), Forces in Mind Trust, and Business. These include partnerships with leading national charities and professional sports clubs. He has also received grants from Health Education England and the AFCFT to develop armed forces community educational modules and materials. During this period, he has published over 40 peer review articles.

Alan established the Royal College of Nursing (RCN) Defence Nursing Forum and  is the RCN link member for military veterans. He is a Courtesy Professor at the University of South Florida, the Assistant Editor of Nurse Education Today, and an international editorial board member of the Journal of Advanced Nursing.  Alan is a Fellow of : the Winston Churchill Memorial Trust; the RCN; the Royal Society of Arts, the faculty of Nursing and Midwifery Royal College of Surgeons Ireland and a Fellow of the American Academy of Nursing where he is a member of their expert panel for Military and Veterans Health.  

Alan is a Chair of the: Armed Forces Network (North West (NW) England), Contact Armed Forces Research Sub-Committee and Cheshire Armed Forces Community Covenant Partnership. He is also a member of the AFCFT Ethics Advisory Panel and the FiMT Research Centre Expert Advisory Board. In 2018, Alan provided evidence to the House of Commons Defence Committee for their Armed Forces and Veterans Mental Health inquiry. In 2022, Alan was inducted into the Sigma Theta Tau International Nurse Researcher Hall of Fame. Alan is a member of the Board of Trustees with Walking with the Wounded.