Abstract: The present disclosure provides a managed pressure drilling method and system that accommodates timely and accurate control of surface pressure in order to maintain appropriate wellbore pressure of a well. The system and method can use a minimal set of inputs, such as a measured pressure input, with a control software hierarchy described herein to improve the accuracy of the controlled pressure and automation of drilling rig components over conventional Managed Pressure Drilling (MPD) systems. Because the method compensates for the real pressure rate of change using the pressure input, the method and system allow the implementation of MPD techniques in legacy applications and drilling rigs. The system and method can reduce human error and inefficiencies that directly degrade the quality of MPD techniques and improve wellbore drilling and hydrocarbon production performance within the industry.