During the European Society for Clinical Nutrition and Metabolism (ESPEN) Congress in Copenhagen, Denmark (September 2016), representatives of the 4 largest global parenteral and enteral nutrition (PEN) societies from Europe (ESPEN), the United States (American Society for Parenteral and Enteral Nutrition [ASPEN]), Asia (Parenteral and Enteral Nutrition Society of Asia [PENSA]), and Latin America (Latin American Federation of Parenteral and Enteral Nutrition [FELANPE]) and from national PEN societies around the world met to continue the conversation on how to diagnose malnutrition that started during the Clinical Nutrition Week, Austin, Texas (February 2016). Current thinking on diagnostic approaches was shared; ESPEN suggested a grading approach that could encompass various types of signs, symptoms, and etiologies to support diagnosis. ASPEN emphasized where the parties agree; that is, that the 3 major published approaches (ESPEN, ASPEN-Academy of Nutrition and Dietetics, and Subjective Global Assessment [SGA]) all propose weight loss as a key indicator for malnutrition. FELANPE suggested that the anticipated consensus approach needs to prioritize a diagnostic method that is available for everybody since resources differ globally. PENSA highlighted that body mass index varies by ethnicity/race and that sarcopenia/muscle mass evaluation is important for the diagnosis of malnutrition. A Core Working Committee of the Global Leadership Initiative on Malnutrition has been established (comprising 2 representatives each from the 4 largest PEN societies) that will lead consensus development in collaboration with a larger working group with broad global representation, using e-mail, telephone conferences, and face-to-face meetings during the upcoming ASPEN and ESPEN congresses. Transparency and external input will be sought. Objectives include (1) consensus development around evidence-based criteria for broad application, (2) promotion of global dissemination of the consensus criteria, and (3) seeking adoption by the World Health Organization and the International Classification of Diseases.