Abstract: Chilled water is produced by an evaporative cooling process. The chilled water is then circulated through a liquid-air heat exchanger to produce a primary air supply of cool-dry air wherein no water is introduced into the cool dry air stream. The primary air supply can be used to cool a space, such as an office, where low humidly is desirable. Additionally, the cool, wet air which is a byproduct of the water-cooling phase can be used as a secondary air supply. The secondary air supply can be used to cool a space where higher humidity is tolerated, such as a warehouse, a garage, a barn, etc. The indirect evaporative cooling system can also be used in conjunction with an air conditioning system to reduce operating costs and increase efficiency.