Radiopharmaceuticals have become essential for advancing cancer treatment. The radio3D project aims to innovate this field by combining radiotherapy with nanomaterials and 3D disease models. This approach seeks to enhance therapeutic strategies while reducing reliance on animal testing for cancer research. The radio3D project aims to enhance cancer therapy efficacy and safety by employing clinically approved nanomaterials and radioisotopes for imaging and treatment of glioblastoma and pancreatic cancer. Advanced 3D tumour models, such as organoids and bioprinted structures, will be utilised to mimic the tumour microenvironment, enabling efficient drug evaluation, investigation of tumour-stroma interactions, and promotion of personalised medicine while minimising animal testing. The initiative comprises four interdisciplinary work packages, each focusing on training, research, dissemination, and management. This structure promotes cooperation amongst various professionals, including chemists, physicists, biologists, physicians, and entrepreneurs. radio3D brings together 21 groups from academia, industry, and hospitals to elevate cancer treatment research, innovation, and ethical standards. Through the interdisciplinary scientific and intersectoral approach and an extensive and targeted training program radio3D is dedicated to cultivating a new generation of interdisciplinary scientists skilled in nanotechnology, radiolabelling, biomedical imaging, and advanced tumour modelling. By harnessing the synergistic potential of nanomaterials and radiopharmaceuticals, while significantly reducing animal testing, radio3D will advance the field by introducing innovative chemistries and alternative methods for understanding cancer biology to establish a groundbreaking benchmark in nanomedical research, transforming the future of oncology and improving therapeutic outcomes.