  The Simons Observatory (SO) is a set of cosmic microwave background
instruments that will be deployed in the Atacama Desert in Chile. The key
science goals include setting new constraints on cosmic inflation, measuring
large scale structure with gravitational lensing, and constraining neutrino
masses. Meeting these science goals with SO requires high sensitivity and
improved calibration techniques. In this paper, we highlight a few of the most
important instrument calibrations, including spectral response, gain stability,
and polarization angle calibrations. We present their requirements for SO and
experimental techniques that can be employed to reach those requirements.
