Ground Substance bridges art, architecture and science through a structural and material model that is at once natural and artificial. The project embeds biological behavior in material systems through the use of advanced technologies in 3D Printing and rapid prototyping.Ground Substance quantifies and spatializes cellular and tissue contour information using normal human mammary epithelial cells cultivated within a 3-D normal or tumor-like microenvironment. The project examines morphogenesis, lumen formation and cellular packing behavior as a response to alterations in tissue surface design. Here, the algorithmic and digital exploration of relationships between interacting cells and their immediate tissue environment gives rise to an abstract, yet deeper understanding of architectural form as it relates to a dynamic boundary condition. Advanced techniques in rapid prototype technology influenced the final production of the model. Prototype studies in 3D printed ceramic modules were also produced. The final fabricated model is composed of 146 unique 3D printed parts connected together with aluminum rod and cable thread.