Public health functions are defined as the purpose of public health interventions, actions, activities and programs. The 'functions' class was developed from the National Public Health Partnership public health core functions 4 and includes both primary and instrumental functions (shown in Table 1 There was reasonable agreement regarding the top levels of the 'health issues' class (although its name was the subject of some debate), and the 'determinants of health' and 'settings' classes. The remaining classes are less well developed and have had limited testing through consultations.