This paper proposes a model for visual communication design that builds on theories of rhetoric and functional literacy. It begins by analysing literature about the interrelationships between design and the theories of rhetoric and functional literacy. Then, a detailed revision of their components serves to develop a transdisciplinary model. Structural similarities among the theories allowed for comparison and identification of relevant elements in four categories: creator/producer, design method, visual information and audience. Finally, a model is proposed selecting the most relevant components for analysis and research in visual communication design.