Ionic liquids, as high‐tech technical fluids, have been in practical application in various fields of technology for several years. The search for ionic liquids suitable for use within hydraulic systems, as another new very important field of technology, has taken more than a decade. The development included the identification of material properties important for usage as a hydraulic fluid, an extensive preselection process and laboratory testing of suitable ionic liquids, as well as long‐term testing using real hydraulic components under real operating conditions. Based on the findings, potential areas of industrial application of ionic liquids as hydraulic fluids are presented, which arise from their extraordinary physicochemical properties. Ionic liquids as high‐tech technical fluids have also made their way into the field of hydraulic drives. With excellent lubricating properties, a wide temperature range, low pour point and vapor pressure, as well as nonflammability and environmental suitability, problems with only one type of fluid, namely, an ionic hydraulic fluid, instead of using different hydraulic fluid types can be solved.