In June 2014, Colorado became the first state to enact a law regulating on-demand transportation network companies (TNCs). Since then, at least 40 other states plus the District of Columbia have established regulatory frameworks for TNCs. Unlike the taxicab industry, TNCs, such as Uber and Lyft, use a digital network service to connect riders to drivers. Drivers use their personal cars for fares and connect with passengers via mobile smartphone apps. This issue brief provides an overview of rideshare service options in Colorado and examines the measure enacted by the General Assembly in the 2014 legislative session addressing the regulation of TNCs.