Tritium is the only one of the radioactive isotopes that a filtering system is unable to neutralize. It is produced by collateral fi ssion processes in nuclear reactors and displays itself in radioactive wastes and effl uents in diff erent forms of tritium oxides. Thus the development and application of nuclear energy entails a challenging problem of treating tritium-containing radioactive wastewater.The paper deals with tritium water isotopologues, namely, with prototritium water and deuterotritium water. Various approaches to the problem of tritium separation have been outlined. The choice of the appropriate process of water detritiation depends, fi rst of all, on whether the detritiated water is recycled back to the reactor system or is discharged to the environment and on whether molecular tritium is to be extracted for further application. Special attention is paid to the process of electrosonochemical water detritiation which is shown to be the preferential one due to its ability to provide molecular tritium. Tritiated water decomposition should be preceded by its concentrating, the latter being two-stage and including water conditioning followed by providing concentrated tritiated water. Reverse-osmosis conditioning and salt rectifi cation are considered as preferential techniques.