Interventions and activities that influence health are often concerned with intangible outcomes that are difficult to value despite their potential significance. Social Return on Investment is an evaluation framework that explores all aspects of change and expresses these in comparable terms. It combines qualitative narratives and quantitative measurements with a financial approach to enable outcomes that can otherwise be overlooked or undervalued to be incorporated appropriately. This article presents Social Return on Investment as an effective tool for supporting the development of a holistic appreciation of how interventions impact on the health and well-being of individuals, communities and societies.