Recognition of the increasing burden of mental illness and the need for mental health promotion is leading researchers to explore ways of assessing the impact of mental health promotion initiatives. In particular, among young people, the impact of mental health promotion in the school setting is being investigated in terms of achieving change that is sustained. This paper argues that potential indicators of success associated with process need to be identified as a way to support schools and project teams as they implement mental health promotion initiatives. A process evaluation of a project to promote resilience in children and primary school communities using a health promotion school (HPS) approach was conducted in Brisbane, Australia, in 2004 and 2005. Aside from differences in the way in which the participating schools structured and implemented their health-promoting school projects, several critical themes emerged that have relevance to mental health promotion projects in school settings. They include the importance of time, the school context and supportive organisational structures, ethos and environment, and building resilience into the curriculum. Other themes indicated the importance of the engagement of the whole school community and of developing partnerships and services, and the usefulness of the health-promoting school framework. Such key factors should be considered in relation to the challenges facing schools that wish to promote resilience, or other concepts related to mental health.