This presentation will discuss strategies for understanding the habitat of remaining oil following a waterflood and provides details of technologies that have been devised to exploit sweep and displacement opportunities. Improving Sweep Efficiency and Displacement Efficiency are usually the two largest factors for improving recovery. But the impacts of improving for specific systems is frequently poorly understood. Understanding the base sweep and displacement characteristics of any oil reservoir waterflood is therefore a necessary precursor to making improvements. In specific systems there is frequently more opportunity in focusing on either sweep or displacement improvement. Strategies for achieving these improvements are described.