The potential advantages of hybrid refractive-diffractive elements in infrared systems are reviewed. It is shown that these advantages can be realized in practice by single point diamond turning. Indeed, their manufacture by this process is no more complex in principle than making conventional aspherics which is a well-established technology. The design and manufacture of a zinc sulphide hybrid lens for the 3 - 5 micron waveband is described.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.