This review provides a perspective on porous silicon (pSi)-based nanomaterials including nanoparticles, nanowires, and thin films, that are currently being used in advanced therapy, imaging, and sensing, with a focus on their effective use in future clinical settings. The achievement of both controlled geometry and architecture, and surface chemistry motifs, are presented as the two key parameters that dictate the nature of interactions with the biological entities. The authors discuss the role of the degradation kinetics in a biological environment into nontoxic by-products. pSi is presented as increasingly fulfilling a central task in various biomedical applications and clinical settings, owing to its unique physiochemical properties.