Health communication is an essential health promotion strategy to convert scientific findings into actionable, empowering information for the public. Health communication interventions have shown positive outcomes, but many efforts have been disappointing. A key weakness is that expert-designed health communication is often overly generic and not adequately aligned with the abilities, preferences and life situations of specific audiences. The emergence of the field of health literacy is providing powerful theoretical guidance and practice strategies. Health literacy, in concert with other determinants of health, has greatly advanced understanding of factors that facilitate or hinder health promotion at individual, organizational and community settings. However, health literacy models are incomplete and interventions have shown only modest success to date. A challenge is to move beyond the current focus on individual comprehension and address deeper factors of motivation, self-efficacy and empowerment, as well as socio-environmental influences, and their impact to improve health outcomes and reduce health disparities.

Integrating participatory design theory and methods drawn from social sciences and design sciences can significantly improve health literacy models and interventions. Likewise, researchers and practitioners using participatory design can greatly benefit from incorporating health literacy principles into their efforts. Such interventions at multiple levels are showing positive health outcomes and reduction of health disparities, but this approach is complex and not yet widespread. This chapter focuses on research findings about health literacy and participatory design to improve health promotion, and practical guidance and case examples for researchers, practitioners and policymakers.