The CSO consists of a 10.4 m diameter Leighton telescope housed in a compact dome located at 4140 m altitude near the summit of Mauna Kea, Hawaii. Instruments are mounted at the Cassegrain and Nasmyth foci for spectroscopy and continuum imaging at wavelengths between 2 mm and 350 μm. Observations are carried out at night. The median zenith precipitable water vapor (PWV) is about 2 mm. Short wavelength (350 μm) observations are possible about 25% of the time, when the PWV is below 1 mm. The telescope is equipped with an active surface adjustment system that improves the surface accuracy to about 13 μm rms. Pointing is about 3″ rms. Observatory computers support both telescope operation and immediate data reduction. The CSO maintains a broad suite of instrumentation and associated data reduction software. Although the CSO staff will provide orientation, inexperienced observers are encouraged to collaborate with instrument teams or experienced observers.