Value and impact are terms that are sometimes loosely defined and used. Assessing and providing evidence of the value and impact of libraries is something that many researchers and practitioners, at least over the last two decades, have tried to address. The reason for great attention to value and impact has been partly the pressure on libraries to demonstrate their value and impact in order to justify their budget or investment by stakeholders. Terms such as value, impact and outcome have been used sometimes interchangeably without clear differentiation. And sometimes they are combined with adjectives such as economic value/impact or social value/impact. The literature on assessing or measuring impact or value of libraries of different kinds (academic, school, public etc.) is extensive and there have already been a few reviews of them such as Debono (2002), Missingham (2005) and Stenstrom, Cole and Hanson (2019).
Value, when used in the context of economic value, is clearer than when it is used in the context of social value. In the economic sense, it might be related to the concepts of Return on Investment or financial value of services. A lot of time value is linked to the perception of users and what is measured as value is how valuable users or stakeholders in general perceive library services to be.
Impact, however, is about change in something. It might be a change in behaviour, ability, skills, or other things. Impact can be negative or positive. In the context of libraries, it is assumed that impact refers to positive impact. We can assume that if something has a value it might have an impact and if something has had a positive impact then it must have some value too.
Having clear definitions of the terms such as value and impact is necessary to ensure clarity of communication between librarians and their stakeholders and policymakers. Librarians use such terms to justify their budget and investment in their resources. While there is a good body of literature on evaluating or measuring value and impact, less has been written on what they mean and what their differences are.
Stenstrom, C., Cole, N., & Hanson, R. (2019). A review exploring the facets of the value of public libraries. Library Management, 40(6/7), 354-367. https://doi.org/10.1108/LM-08-2018-0068
Missingham, R. (2005). Libraries and economic value: a review of recent studies. Performance measurement and metrics, 6(3), 142-158. https://doi.org/10.1108/14678040510636711
Debono, B. (2002). Assessing the social impact of public libraries: What the literature is saying. Australasian public libraries and information services, 15(2), 80-94.