  The XENON100 experiment, in operation at the Laboratori Nazionali del Gran
Sasso (LNGS) in Italy, was designed to search for evidence of dark matter
interactions inside a volume of liquid xenon using a dual-phase time projection
chamber. This paper describes the Slow Control System (SCS) of the experiment
with emphasis on the distributed architecture as well as on its modular and
expandable nature. The system software was designed according to the rules of
Object-Oriented Programming and coded in Java, thus promoting code reusability
and maximum flexibility during commissioning of the experiment. The SCS has
been continuously monitoring the XENON100 detector since mid 2008, remotely
recording hundreds of parameters on a few dozen instruments in real time, and
setting emergency alarms for the most important variables.
