Since 1974, Siemens' Power Generation Group (KWU) has been operating a high-pressure two-phase flow test loop-called the Benson test rig-which offers a range of operating conditions that is unique in the world (1 to 330 bar, 20 to 600°C, and 0 to 2 MW electric heating power). The 25th anniversary of the first tests performed at this test rig presents a good occasion not only for reviewing the past, but also for contemplating the future of two-phase flow experiments. The past was characterized by integral and separate effect tests for power generation using nuclear, fossil, and renewable energy sources as well as for process industries. This article will present examples demonstrating the flexible and broad range of applications for the Benson test rig. The results of the tests have been used to develop algorithms for implementation in computer programs and also for validating such programs. Usually these computer programs-so-called analysis tools-are used for analyzing systems or components. From an analyst's point of view, two-phase flow experiments serve either to verify global flow conditions or to supply inputs such as boundary conditions and material laws and/or initial conditions for the analysis tools. An advanced way of making sure that all available knowledge can be input into the analysis tools is to collect and store it in a program system from which it can be called up, whenever required, according to the task in hand. Siemens' KWU Group has started developing such a system. Apart from integral tests conducted for new power plants, future two-phase flow experiments will probably focus on expanding this program system's database.