The Association of Principal Fire Officers or APFO is a British Trades Union. Membership is open to Chief Fire Officers, Assistant Chief Fire Officers and Deputy Assistant Chief Fire Officers employed by Local Authority Fire Brigades in England and Wales,
Firemasters and Assistant Firemasters employed by ditto in Scotland and the Chief Fire Officer and Assistant Chief Fire Officers of the respective Fire Authorities for Northern Ireland, the Isle of Man and the Channel Islands.
It exists to represent its members in negotiationg pay, pensions and conditions of service as well as in disciplinary and legal matters, and is an entirely separate organisation from the similarly named Chief and Assistant Chief Fire Officers' Association or CACFOA.