The National Documentation Centre on Drug Use (NDC) (now the HRB National Drugs Library), Ireland's drugs library, is a unique information resource that embraces elements of several library types: national, public, special, academic, digital, and health.

This article presents the results of an evaluation study carried out by NDC staff. Both quantitative and qualitative methods were used to examine aspects of the value and impact of the NDC’s resources and services.

Based on the views and experiences of respondents, we can say that the NDC's services and resources are valued by our users and have had positive impacts on their work. These impacts have been wide-ranging and have brought about affective, knowledge-based, behavioural, and competence-based change in practice. The study provides the NDC with a significant body of evidence on which to base plans for the development of resources and services over the next few years.