I first met Paul Castle in 1985. Having just been appointed as the Regional Dental Officer for the North Western Regional Health Authority, it was suggested that I join the newly formed Regional Fluoridation Action Group, which was having its inaugural meeting the following Monday. I duly arrived, met Paul Castle, started a lifetime interest in water fluoridation, and a friendship that was to last some 30 plus years. It quickly became apparent that Paul had some real gifts including the ability to turn complex scientific concepts into readable prose.

It is perhaps worth looking back to the 1960s to understand how Paul first acquired those skills. He graduated in 1968 with a first class honours degree in history from Pembroke College, University of Oxford. Far from the popular concept of history as the chronology of kings and queens, a history degree ensures a graduate posesses: '- a talent for clear expression, both oral and written [...] - gathering, investigating and assessing material [...] - and organising the material in a logical and coherent way' (theguardian.com, 15 January 2010; What to do with a degree in history).

Paul certainly learnt those skills and went on to hone them firstly as a journalist and later as a local politician. One of his early journalistic posts was as a leader writer for the Liverpool Daily Post, a well-respected and influential regional newspaper. Paul was subsequently elected to Sale Council and stood unsuccessfully as the Labour Party candidate for the Cheadle constituency.

Paul then joined the NHS to head the Regional Public Relations department for the West Midlands RHA, where he worked with John Charlton and John Langford. Subsequently he moved to the North Western RHA, joining John Roberts who had been appointed Regional Administrator. Both Paul and John had shared interests in health promotion and were very active in tobacco control and in promoting water fluoridation. I feel water fluoridation in the North West would have been long achieved if it had not been for the intransigence of the newly privatised water company concerned.

Paul moved back to the West Midlands where he set up his own company, Castle Communications. I continued to work with him for the British Fluoridation Society; his report One in a million, now in its third edition, is a testimony to his energy and commitment. He is survived by his wife Pamela, a former dental nurse, two children and one grandson; they will miss him sorely, as will I.