An overview is given of ongoing work in desiccant cooling under the US solar heating and cooling research programme. Open cycle adsorption systems are examined. The basic operating principles of each dehumidifier concept are explained and compared. Performance predictions for a solar desiccant solar system employing an axial-flow desiccant wheel dehumidifier are presented which indicate that it should be beneficial to use solar desiccant coolers in residential applications. Test results are expected within one year.