For the first time, the IAEA convened an international conference dedicated exclusively to nuclear forensics. Experts, senior officials and policy makers from more than 76 Member States and eight organizations with established or emerging capabilities in nuclear forensics participated. The conference recognized the important role of nuclear forensics as part of a nuclear security infrastructure to include support to law enforcement investigations and nuclear security vulnerability assessments. The proceedings provide a summary of the conference deliberations, outcomes and conclusions, as well as an outlet for contributed scientific papers and posters that represent nuclear forensic state of practice. Papers address the role of nuclear forensics in a nuclear security infrastructure, the elements of a nuclear forensic examination, confidence in findings, development and sustainability of a nuclear forensic capability at the national level, lessons learned from case studies and other applications, international cooperation with scientific and law enforcement partners, as well as assistance available in nuclear forensics from the IAEA, upon request, to include technical guidance, training, and research.