This paper examines the merits of coupling a desiccant dehumidification subsystem to a gas-engine-driven vapor-compression air conditioner. A system is identified that uses a rotary, silica gel, parallel-plate dehumidifier. Dehumidifier data and analysis are based on recent tests. The dehumidification subsystem processes the fresh air portion and handles the latent portion of the load. Adding the desiccant subsystem increases the gas-based coefficient of performance 40% and increases the cooling capacity 50%. Increased initial manufacturing costs are estimated at around $490/ton ($140/kW) for volume production. This cost level is expected to reduce the total initial cost per ton compared to a system without the desiccant subsystem.