Guidance in the UK requires the co-ordination and standardisation of services to protectadults from abuse. However, there remains considerable ambiguity about the basic conceptsof abuse and vulnerability. This paper reports an empirical study of factors in professionaldecision making in relation to identifying and reporting abuse of older people.A systematic review and a panel of expert practitioners were used to identify factors thatmight influence professional recognition and reporting of elder abuse. These factorswere incorporated into a questionnaire that included randomised factorial survey vignettesand additional questions on decision making. Sets of unique vignettes were completedby 190 social workers, nurses and other professional care managers acrossNorthern Ireland in 2008, giving 2,261 randomised vignettes used as the units of analysis.Recognition and reporting were influenced by case factors specific to the abuse eventwhile contextual factors did not significantly influence recognition or referring ofabuse. This study has shown that the factorial survey can be a powerful tool to investigateprofessional decision making. It provides an insight into practitioners’ responses tocomplex ethical dilemmas. The findings are considered within the context of currentpolicy and the need for further research is discussed.