For industrial-scale CO 2 injection in saline formations, pressure increase can be a limiting factor in storage capacity. To address this concern, we introduce Active CO 2 Reservoir Management (ACRM), which combines brine extraction and residual-brine reinjection with CO 2 injection, contrasting it with the conventional approach, which we call Passive CO 2 Reservoir Management. ACRM reduces pressure buildup and CO 2 and brine migration, which increases storage capacity. Also, “push-pull” manipulation of the CO 2 plume can counteract buoyancy, exposing less of the caprock seal to CO 2 and more of the storage formation to CO 2 , with a greater fraction of the formation utilized for trapping mechanisms. If the net extracted volume of brine is equal to the injected CO 2 volume, pressure buildup is minimized, greatly reducing the Area of Review, and the risk of seal degradation, fault activation, and induced seismicity. Moreover, CO 2 and brine migration will be unaffected by neighboring CO 2 operations, which allows planning, assessing, and conducting of each operation to be carried out independently. In addition, ACRM creates a new product, as extracted brine is available as a feedstock for desalination technologies, such as Reverse Osmosis. These benefits can offset brine extraction and treatment costs, streamline permitting, and help gain public acceptance.