Advances in the field of tissue engineering are increasingly reliant on biomaterials that instruct, rather than simply permit, a desired cellular response. One area of recent focus has been development of approaches to replicate or induce regenerative healing of dynamic, spatially patterned or inhomogeneous structures within the body. Such materials would have to direct the bioactivity of multiple cell types in spatially or temporally varying patterns. For example, while many efforts in orthopaedic tissue engineering focus on the repair of single tissues, injuries often occur at the interface between tissues. Many of these defects are at the junction between soft tissue and bone, and contain overlapping patterns of extracellular matrix (ECM) proteins, mineral content, structural alignment and biochemical signals that are often not regenerated following injury. This session welcomes submissions from academia, clinicians and industry on innovative biomaterial approaches for guiding multilineage cell fate in vitro and the repair of tissue interfaces in vivo. Topics can address fundamental challenges and current progress in the design, fabrication and characterization of biomaterials that can simultaneously guide multiple cell behaviors (e.g., proliferation and differentiation); biomaterials with spatially graded properties mimicking native tissue interfaces; and biomaterials improvement of host tissue integration.