Guideline development groups are an integral part of evidence-based healthcare and will remain so for the foreseeable future. There is a need for the efficient production of high-quality guidelines both to ensure high standards of care and to conserve resources. Social psychological research on group processes provides valuable information that can be applied to studying the functioning of guideline development groups, including the methods they use to develop recommendations. This article describes four key concepts in the group process literature: information sharing, systematic processing, group development, and group potential productivity. We evaluate their importance for guideline development groups and conclude with methodological suggestions for the study of these complex processes.