It is a central feature of current Norwegian health and social care policy to see informal carers as active partners. However, research has revealed that carers often experience a lack of recognition by professionals. In 2010, the Norwegian Directorate of Health initiated a web-based competence-building programme (CBP) for health and social care practitioners aimed at facilitating collaboration with carers. The programme comprised case presentations, e-lectures, exercises and topics for discussion, and was introduced in 2012. It was flexible and free of charge. This article is based on a study (2012–2013) that followed the piloting of this CBP in four settings. The study aimed to explore factors that influenced the implementation of the programme and whether or not using it affected health and social care practitioners’ attitudes and perceived capacity for collaboration with carers. The study employed a mixed-methods design. A questionnaire was distributed to all staff before and 5 months after the CBP was introduced, followed by focus group interviews with a sample of staff members and individual interviews with the leadership in the involved settings and those who introduced the programme. The quantitative data were analysed using descriptive statistics, which subsequently formed the basis for the focus group interviews. The qualitative data were analysed by means of content analysis. The programme's introduction was similar across all research settings. Nevertheless, whether or not it was adopted depended to a large extent on leadership commitment and engagement. In settings where the programme's use was monitored, supported by management and formed part of on-the-job training, there seemed to be a positive impact on staff attitudes concerning collaboration with carers. Participant staff reported that their awareness of, motivation for and confidence in collaboration with carers were all strengthened. In contrast, the programme was of minimal benefit in settings with low leadership engagement.