This document complements the recommendations to establish and sustain health promotion in schools set out in the Guidelines to Promote Health in Schools document. It is an advocacy document for the health and education sectors to undertake school health promotion activities based on the evidence of effectiveness. The document provides succinct evidence-based arguments to support the need for school health promotion and advocates for a whole school (Health Promoting Schools) approach to strategically plan and implement school health initiatives. The content includes brief summaries of the latest evidence of effectiveness in building the health knowledge, behaviours and competencies in young people to prevent non-communicable diseases. It is intended to address policy and decision-makers and education officials in a manner that is understood and applicable to both sectors.