This paper reports the outcome of the Galway Consensus Conference, an effort undertaken as a first step toward international collaboration on credentialing in health promotion and health education. Twenty-nine leading authorities in health promotion, health education, and public health convened a 2-day meeting in Galway, Ireland, during which the available evidence on credentialing in health promotion was reviewed and discussed. Conference participants reached agreement on core values and principles, a common definition, and eight domains of core competency required to engage in effective health promotion practice. The domains of competency are catalyzing change, leadership, assessment, planning, implementation, evaluation, advocacy, and partnerships. The long-term aim of this work is to stimulate a global dialogue that will lead to the development and widespread adoption of standards and quality assurance systems in all countries to strengthen capacity in health promotion, a critical element in achieving goals for the improvement of global population health.