The primary objectives of this guide are to show the benefits of measuring the effects of program activities and services, so as to improve both program operations and outcomes for women survivors of violence, as well as to provide guidance for designing and implementing data systems that function efficiently and effectively to achieve the goals of the organization. The guide demonstrates how five principles of performance measurement used in the corporate, government, and nonprofit sectors can be applied to programs that target violence against women. The five principles are to measure what is important for achieving the goals of the organization; focus on a few vital measures, rather than on every aspect of the project that someone might want to consider; measure to improve performance, not just to report it; measure outcomes, not just outputs; and measure initial, intermediate, and long-term outcomes. Key elements in planning a competent data system are to establish a technology steering committee, project teams, and working groups; define and communicate the project goals and scope; and develop a project implementation plan. In explaining the implementation of a competent data system, the guide focuses on developing the system design, managing implementation, training for system users, and continued planning. A list of 26 resources and a sample technology planning worksheet.