The surface of a biomaterial is the interface between the biomaterial and the biological environment it is placed in. Thus, it is essential to properly and precisely engineer the surface chemistry and structure of a biomaterial to optimize its performance in biological applications. Surface characterization of these engineered surfaces and interfaces is required to determine if the desired surface chemistry and structure was obtained. This workshop will provide an overview of the fundamentals of surface modification and characterization along with latest developments and challenges in these fields. The capabilities and new directions of ESCA for the characterization of biomedical nanoparticles along with ToF-SIMS for 3D mass spectral imaging of biological materials will be emphasized. The latest strategies for engineering biomaterial surfaces and the corresponding surface characterization challenges of analyzing those modified surfaces will also be emphasized.