The Internet is increasingly prominent as a source of health information for people with multiple sclerosis (MS). But there has been little exploration of the needs, experiences and preferences of people with MS for integrating treatment information into decision making, in the context of searching on the Internet. This was the aim of our study.Sixty participants (51 people with MS; nine family members) took part in a focus group or online forum. They were asked to describe how they find and assess reliable treatment information (particularly online) and how this changes over time. Thematic analysis was underpinned by a coding frame.Participants described that there was both too much information online and too little that applied to them. They spoke of wariness and scepticism but also empowerment. The availability of up-to-date and unbiased treatment information, including practical and lifestyle-related information, was important to many. Many participants were keen to engage in a 'research partnership' with health professionals and developed a range of strategies to enhance the trustworthiness of online information. We use the term 'self-regulation' to capture the variations in information seeking behaviour that participants described over time, as they responded to their changing information needs, their emotional state and growing expertise about MS.People with MS have developed a number of strategies to both find and integrate treatment information from a range of sources. Their reflections informed the development of an evidence-based consumer web site based on summaries of MS Cochrane reviews.