Over the life of a typical vehicle, a average can be expected to apply the brakes on the order of 1.6 million times – almost 9 times per mile and over 290 times per day, and an “exuberant” driver can be expected to do this over 2.2 million times. Without question, the driver becomes accustomed to how the vehicle responds to braking control (and all of the normal variation around it), and even develops expectations for how it will respond the next time the brakes are employed. In the rare event of a failure or malfunction in the brake system, that results in an appreciably different vehicle response to the brake brake input, this can be surprising and even alarming to the driver, sometimes to the extent of causing hesitatation in braking. Fortunately, with the rise of mechatronic braking actuators in the 1980’s and 1990’s, features such as “Driver Brake Assist” (which provides additional pressure beyond what the primary brake actuator can at the time) and “Panic Brake Assist” (which provides additional pressure beyond what the driver is requesting for brake apply rates above a calibratable threshold) could be developed in the decade after, using the new brake actuator (the hydraulic pump in the anti-lock brake unit) to provide additional assist to the driver if needed. The vehicles of today will often have multiple actuators capable of providing deceleration, including a mechatronic (or vacuum) brake booster, regenerative braking, electric parking brake actuators, and in some cases a secondary brake module. With these added degrees of freedom, comes added opportunity to improve performance and therefore the driver’s confidence in the vehicle’s braking capability, but also added complexity. With actuators able to increase - depending on their installation - braking on the front axle, the rear axle, or both, and with the ability to suppress hydraulics via valve control to reduce pedal travel important conderations for brake balance and vehicle stability arise, which must be balanced with straight line performance and brake feel. The present work briefly examines the history of “deceleration adders” (supplemental brake actuators used to improve performance in certain operating conditions such as system failures), draws from published information to establish a framework the performance necessary to maintain the driver’s confidence, and discusses different actuator types and control strategies along with considerations for integrating them into the brake system.