ISOTOPIC provides a practical solution to a wide range of gamma-ray radiation measurement problems encountered in site characterization and waste container measurements. The easy-to-use software is based on work done originally at several U.S. Department of Energy (DOE) sites in the analysis of thousands of fissile waste containers and in methods developed at the U.S. Energy Measurements Laboratory (EML-NYC) for measuring wide-area contamination of soils and surfaces. ISOTOPIC operates under the latest 64-bit operating systems, and supports the vast majority of ORTEC spectroscopy hardware offerings. In particular, ISOTOPIC forms the software element of the exciting ISO-CART-85 mobile low level waste assay system. ISOTOPIC places emphasis on practicality, flexibility and defendability of results through the use of traceable calibrations.