In this two part series we provide a Basic SFC Primer for the chromatographer. Supercritical Fluid Chromatography (SFC) has been utilized in various forms in the last 50 years and improvements in instrumentation and column technology have led to the growth of the technique over the last decade. The first part of this series will review the mobile phase characteristics, mobile phase modifiers/additives and basic column characteristics. Part 2 will cover the role of the stationary phase, column selection and sample considerations.