The IAEA Desalination Thermodynamic Optimization Program DE-TOP, a newly developed tool for thermodynamic analysis of coupled nuclear power and seawater desalination plants, was released early this year. This software is capable of analyzing different coupling options including power generation systems coupled to desalination systems through various alternatives of steam extractions. The advantages and disadvantages of each coupling on the overall power cycle can be analyzed based on detailed models in DE-TOP. General description of DE-TOP structure is made and main features are highlighted. Benchmarking of DE-TOP with cases found in literature demonstrated satisfactory results. (C) 2011 Elsevier B.V. All rights reserved.