The dynamic nature of psychosocial interventions implies that trying to measure their effects using standardised clinical trial measures may not capture their full effects. Rich and valuable data during the sessions may be missed by using standard quality of life questionnaires. This paper compares observational measures in the context of recording the well-being of a person with dementia during and outside of a visual arts intervention. A literature search was conducted using systematic principles of searching, screening and retrieval to identify peer-reviewed English language evaluations of research projects using observational measures with people with dementia. Psychometric properties, strengths and weaknesses of 11 observational tools are reviewed in order to identify the most appropriate one for evaluating a visual art intervention for people with dementia. This review supports the Greater Cincinnati Chapter Well-Being Observation Tool as an appropriate measure to evaluate a visual art programme for people with dementia. The results of this review will help researchers plan projects to show the full range of effects for people with dementia for taking part in art sessions.