A mechanical ventilation system should be designed to provide a minimum amount of outdoor air to each space, based on occupancy number and building area, according to ANSI/ASHRAE Standard 62.1-2010, Ventilation for Acceptable Indoor Air Quality (ASHRAE 2010c). Demand-controlled ventilation (DCV) can be used to reduce unnecessary ventilation and save energy when a space is occupied at less than its design level. Carbon dioxide sensing could be used to estimate the number of people in a space or the strength of occupant-related contaminant sources. This control approach is called CO2-based DCV. CO 2-based DCV is based on several assumptions, which should be validated for the application of CO2-based DCV. This paper describes the results of a literature search performed to review these assumptions. The study concludes that the assumptions are valid and that CO2-based DCV can meet the objectives of ANSI/ASHRAE Standard 62.1-2010.