This article describes an organization that was established in 1995 in order to help investigators figure out how to deal with radioactive crime scenes. The organization is called the Nuclear Forensics International Technical Working Group, or ITWG for short. The organization is a great help because it creates real life exercises for investigators to complete and does research to figure out new skills and techniques for those investigators for the past 18 years. The exercises use actual materials from the nuclear life cycle. The materials that they have used so far include reactor-grade plutonium oxide, low enriched uranium oxide, and highly enriched uranium metal and oxide. ITWG’s main goal is to further the knowledge of the science and use of nuclear forensics and to provide a new common way of aiding investigators. In a radioactive crime scene, the investigators need to be able to figure out the origin of the material or if it was a man-made material, and how it was created. This could really help solve to which area they were stolen, or if not stolen then possibly where it fell out of regulatory control. If they figure out those, then it could help with finding vulnerabilities with the systems that are trying to protect the material and fix them. Overall, there are only a few labs that can help investigators with these questions.The group is made up of nuclear forensics practitioners, including scientists, law enforcement officials, regulators and policymakers all of whom have connections with government officials. So far, there has been over 5 Collaborative Materials Exercise that were discussed at the American Chemical Society’s national meeting, which is where ITWG goes to discuss their findings. The last meeting took place August 24th 2017 in Washington D.C. The Exercise Task Group, which is the group that is responsible for creating all the different scenarios, meets every two to three years to send out small amounts of radioactive materials to the labs to inspect and report about the materials back to the ETG (Exercise Task Group). They do things such as physical characterization, elemental and isotopic analysis and radiochronometry. Jon Schwantes is a senior scientist at the Department of Energy’s Pacific Northwest National Laboratory, who has been creating the exercises for ITWG since the year 2009. He is going to present the final results at the CMX-5 (which already happened). At the beginning of it all, there were only six lab that partook in the exercises. This year, 20 labs were there in CMX-5. The newest exercises will be begin in the fall of 2018, with an expecting 25 labs to be present this time from upto 21 different countries, which one includes DOE’s Lawrence Livermore National Laboratory. Overall, this does seem like a really good idea. We don’t want radioactive materials to be created in the wrong hands. The group has been doing good so far.