Discussion: Many of the most significant clinical advances have resulted from work conducted directly by pharmaceutical companies or sponsored by them. The industry is one of the most highly regulated in the worid and the demands made to ensure quality have forced companies to change the way they work with external investigators. Once seen as customers, they are now considered more as suppliers and this has changed the nature of the relationship with the external researcher. Generating good data, the best evidence, is vital for the success of a new medicine and its contribution to patient care. Evidence-based Medicine will change how clinical trials are planned, conducted, analysed and published and it has already become another influence to help shape the collaboration between investigator and industry sponsor.