Cleanroom air conditioning plays a significant role in applications starting from food and beverages, health care, pharmaceutical, optics, bio safety, semiconductor and electronics applications. It also plays a key role in special applications for sector like defense, research and space technology. The present paper discusses the important aspects to be taken into considerations during air conditioning for cleanrooms. In addition to control of temperature and humidity, cleanroom air conditioning also involves control of air borne particles, air flow pattern, room pressurization, etc. The paper also addresses important issues such as energy conservation and cleanroom performance testing. The present study gives an insight towards efficient designing of cleanroom air conditioning.