Abstract. This study combines Web usage mining, Web link analysis, and bibliometric methods for analyzing research activities in research organizations. It uses visits to the Expert Protein Analysis System (ExPASy) server—a virtual research infrastructure for bioinformatics—as a proxy for measuring bioinformatic research activity. The study finds that in the United Kingdom (UK), Germany, and Spain the number of visits to the ExPASy Web server made by research organizations is significantly positively correlated with research output in the field of biochemistry, molecular biology, and genetics. Only in the UK do we find a significant positive correlation between ExPASy visits per publication and the normalized impact of an organization's publications. The type of indicator developed in this study can be used to measure research activity in fields in which e-research has become important. In addition, it can be used for the evaluation of e-research infrastructures.