There is little doubt that CO2 will play a bigger role as a propellant for aerosols. Legislation and market sentiment drive a need to reduce the use of hydrocarbon propellants and replace them with more sustainable alternatives. CO2 has unique features, but developing and manufacturing aerosols based on CO2 has its challenges. This presentation will explain the theory, the pros and cons, the challenges, and the technologies available as a starting point for further discussion, and the transition to more sustainable aerosols