Data warehouse (DW) is a collection of integrated databases designed to support managerial decision-making and problem-solving functions. It contains both highly detailed and summarized historical data relating to various categories, subjects, or areas. All units of data are relevant to appropriate time horizons. DW is an integral part of enterprise-wide decision support system, and does not ordinarily involve data updating. It empowers end-users to perform data access and analysis. This eliminates the need for the IS function to perform informational processing from the legacy systems for the end-users. It also gives an organization certain competitive advantages, such as: fostering a culture of information sharing; enabling employees to effectively and efficiently solve dynamic organizational problems; minimizing operating costs and maximizing revenue; attracting and maintaining market shares, and; minimizing the impact of employee turnovers. If you’re a leader in a defense or security agency, it’s becoming more and more common that those at your level have access to all kinds of data about your organization – personnel data, budget data and competitor data, just to mention a few.