The treatment of critical-size defects—too large to heal naturally—is typically approached with invasive surgical procedures or external fixation devices, with the associated long rehabilitation times, emotional exhaustion, and high failure rates. This project aims at creating self-assembling implants capable of inducing tissue and bone regeneration in critical-size defects using minimally invasive procedures. The implants will feature a frame of superelastic and shape-morphing NiTi wovens, with the ability to fold for facilitating insertion and unfold after placement. The geometry of the NiTi structure will be custom-designed to meet the dimensions of the defects and define the healing volume. After inserting and unfolding the frame, the core of the implant will be filled with stimuliresponsive and anti-bacterial hydrogels, and self-assembling piezoresistive and electromagnetically functional structures for stimulation, sensing and monitoring. The implant will be completed with the incorporation of cells, spheroids and organoids to act as versatile cell sources and enable tissue regeneration. The project builds upon expertise from the host institution in additive manufacturing (AM) of NiTi employing laser powder bed fusion and from the candidate in the 3D and 4D printing of stimuliresponsive electroactive composites. It will contribute to the research line on materials for healthcare from the host institution and to its research program on advanced materials processing. The host institution will benefit from an expanded portfolio of materials and technologies, especially as regards the printing of piezoresistive and electromagnetically functional structures, while the candidate will expand his background on biomedical applications of AM and initiate a personal research line on smart materials for health in an international environment. A set of conceptual case studies in connection with critical-size defects in osteosarcoma will be developed as demonstrators.