The aim of the VIVOS project was to develop and evaluate methodologies, i.e. sets of methods, for determining the value and impact of 'virtual outreach’ information services, in the health sector in the UK. Five different projects were recruited initially, with another two added later. Methods were largely qualitative, with over 130 interviews conducted among health professionals, complemented by postal questionnaire surveys. Identified factors impacting on the successful roll-out and continued development of the projects included the need for help-desk type services, to provide sustained support for new users to the services. Follow-up of the projects 18 months after the end of the VIVOS project revealed that the long-term impacts for the participating library managers included the benefits of using evidence on service outcomes, enhanced recognition locally and greater confidence in evaluation.