This paper examines the scope of practice of global health, drawing on the practical experience of a global health initiative of the Government of Canada--the Teasdale-Corti Global Health Research Partnership Program. A number of challenges in the practical application of theoretical definitions and understandings of global health are addressed. These challenges are grouped under five areas that form essential characteristics of global health: equity and egalitarian North-South partnerships, interdisciplinary scope, focus on upstream determinants of health, global conceptualization, and global health as an area of both research and practice.