ISO 16439:2014 defines terms for impact assessment of libraries and specifies methods for such assessment: for the purpose of strategic planning and internal quality management of libraries; to facilitate comparison of library impact over time and between libraries of similar type and mission; to promote the libraries' role and value for learning and research, education and culture, social and economic life; to support political decisions on levels of service and strategic goals for libraries.

ISO 16439:2014 considers the impact of libraries on individuals, institutions and society. It is applicable to all types of libraries in all countries. However, not all methods described apply to all libraries. Limitations on the applicability of individual methods are specified in the descriptions.