This paper discusses the use of dry and liquid desiccant technologies and how to apply them creatively for the treatment of outside air. This includes a passive desiccant wheel design and a liquid desiccant design that utilizes a combination of cooling tower water, chilled water and hot water. The liquid desiccant system modulates with the outside air loads to either cool or heat the liquid desiccant to provide dehumidification or humidification of the outside air. Waste heat or on-site power generation would also be used to regenerate the liquid desiccant solution. A comparison of the technologies and the opportunities for both to provide comfort and energy savings to meet ventilation codes will be presented.