Purpose – The purpose of this paper is to present some of the results of the project “Evaluating the usage and impact of e-journals in the UK”. The particular research reported here evaluated the use of the ScienceDirect journals database with regard to Life Sciences, Economics, Chemistry, Earth & Environmental Sciences and Physics by ten major UK research institutions. The aim of the study is to investigate researchers' digital behaviour, and to ascertain whether their use and behaviours varied by subjects and disciplines, or in relation to the institutions in which they worked. Design/methodology/approach – Raw logs for ScienceDirect were obtained for the period January to April 2007, were subject to deep log techniques and analysed using the Software Package for Social Sciences (SPSS). Findings – Typically, 5 per cent of the ScienceDirect journals viewed accounted for a third to half of all use. A high proportion of researchers entered the ScienceDirect site via a third-party site, and this was especially so in the case of the Life Sciences and in the highest-ranked research institutions. There were significant institutional and subject differences in information-seeking behaviour. In the most research-intensive institutions, per capita journal use was highest and their users spent much less time on each visit. There were significant differences of the order of 100-300 per cent in the age of material viewed between subjects and institutions. Just four months after ScienceDirect content was opened to Google indexing, a third of traffic to the site's Physics journals came via that route. Originality/value – The research is one of the very few studies to investigate subject and institutional differences with regard to the information seeking and use of UK researchers, something UK academic librarians should particularly welcome.