Implementing a cost-effective and meaningful ethylene oxide (EtO) environmental monitoring program is more than purchasing an EtO sensitive device and placing it in the department or on an employee. First, the responsible person involved in such a program must have some general knowledge of analytical procedures and methods. Second, the individual should possess an understanding of the various types of equipment that are available and their limitations. Third, and perhaps most importantly, there must be a good thorough understanding of ethylene oxide and the principles of environmental monitoring as it relates to employee exposure. Even if the hospital or department decides to contract with an outside vendor to perform these services, the responsible individual must be involved with the provider from the inception of the program. All too often, departmental managers enter into an ethylene oxide exposure monitoring program with little thought to where, when, or how to monitor. The key to any ethylene oxide exposure monitoring program has to be the measurement of the extent of employee exposure. Once this is established, the monitoring program can be developed.