Purpose: The purpose of the paper is to research the stress caused to small to medium-sized enterprise (SME) staff by online collaboration. It aims to investigate online team roles as possible stressors. Design/Methodology/Approach: The paper is based on research carried out on online collaborative teams by the authors in the Open University Business School, and on existing literature on stress and collaboration. The paper uses MTR-i[TM], a commercially used team role analysis tool, and Myers-Briggs personality types to postulate reasons for stress caused by online collaboration in SMEs. Findings: If team roles are not taken into account then the entrepreneurial members of an SME team may well find online collaboration stressful and so may not be able to fully participate in collaboration, or support others to do so. Research Limitations/Implications: The limitations of the research are that so far the research has been carried out on relatively small numbers. A much wider scale study is needed. Practical Implications: The research so far indicates that online collaborative learning in SMEs (whether formal, or informal) needs to take into account the team roles usually carried out by individuals at work if full use is to be made of in order to optimise online collaboration. Originality/Value: This paper links Myers-Briggs personality types to the ability of SMEs and entrepreneurs to collaborate online. It will inform educators and SME entrepreneurs.