Want to keep up with simulation methods in ionizing radiation? Do you develop simulation codes, or use codes like MCNP, GEANT, TOPAS, FLUKA, openMC, SRIM/TRIM McBEND, TRIPOLI? Are you working or studying in the fields of physics, nuclear engineering, medical physics, health physics, computation? Are you involved with medical therapy, security, radiation detectors, imaging, nuclear plants, fusion , accelerators? Organizers review membership requests and admit those involved in the field and those who aspire to be. Professionals, academics, researchers and students are welcome.