This paper proposes a marketing planning framework that will assist managers to address sustainability challenges in their decision making, in line with the American Marketing Association's (AMA) revised (2007) definition of marketing, which calls for a responsibility to society at large, not just individual consumers. At present, marketing's conceptual frameworks lag behind what is a fundamental and significant shift in marketing philosophy. We propose a Sustainability Marketing Model, a simple yet systematic framework that ensures sustainability cascades through the marketing planning process. In developing this, the marketing mix is replaced with a matrix that adds four critical decision fields to the traditional marketing mix - Participants, Physical Evidence, Process and Partnership - and draws on the three pillars of sustainable development - Planet, People and Profit - to ensure managers cross-check decision-making's sustainability impacts. The model is described, and implications for theory and practice, and potential directions for further research, are discussed.