During construction, ENERGOPROJEKT PRAHA acted as the investor's design supervisor, overseeing project changes during construction. Since the Temelín Nuclear Power Plant was put into operation, ENERGOPROJEKT PRAHA has been a major supplier of technical assistance, modifications to the initial project, preparation of project documentation for project approval, preparation of documentation for construction, expert opinions, safety documentation, implementation of stress test measures, increasing unit output, participation in periodic safety assessments, and preparation for the construction of additional units at the site.