Public health has been an enormously effective instrument for improving life expectancy and quality of life. Historically a sphere of governmental activity led by physicians and staffed by sanitarians and nurses, public health has evolved to become a multi-facetted field of societal activity. It engages many agencies and community action in reducing infectious and non-communicable diseases as well as many aspects of lifestyle and health equity. Education for an adequate professional workforce is one of its key functions. Schools of public health have fulfilled this role only partly even in developed countries, but in countries in transition and in low-income countries the problem is much more acute. We discuss the role of mentoring of new schools calling for strong public and private donor support for this as a key issue in global health.