Simultaneous color contrast, the illusion of change in a physically constant color, is often explained as resulting from color relationships only, with little or no acknowledgment of the importance of shape relationships to the illusory effect. Taking the standard color interaction chart as the point of departure, the author identifies compositional features that are both necessary to and optimal for simultaneous color contrast illusions. A typology of compositional organizations is proposed, along with a diagrammatic system for mapping the color interactions. The four compositional types, simple-uniform, simple duo-form, complex uniform, and complex duo-form, are examined through diagrams and examples of the author's paintings and digital prints. The explication of compositional features, compositional types, and diagrams offers new strategies for artists to structurally integrate color and composition.