To share the existing, albeit limited, experience among nations and to explore the feasibility of international collaboration on the identification and early evaluation of health care technologies, an workshop was arranged in September 1997. Twenty-seven policy makers and researchers from twelve countries attended the meeting and concluded that: the policy environment in most European countries is characterized by insufficient data on safety, effectiveness, and cost-effectiveness of health care innovations; that an early warning system is perceived as an essential mechanism for facilitating communication among policy makers, technology experts, and health professionals; and that collaboration on early warning activities might be even more useful than traditional collaboration in health technology assessment.