The latest transmission electron microscopes with field emission guns and imaging filters now provide much of the microanalysis and imaging necessary in applications such as ULSI device development. The installation and operating environment of the instruments are critical to their successful operation. Information from two such installations is presented here, one in a purpose built facility and the other in an existing building. Ground vibration, acoustic noise, stray electromagnetic fields, air flow and temperature variation are considered, and the measures implemented to achieve desirable levels of each parameter are discussed. The physical layout of an installation is also shown.