Information visualization has proven to be a valuable tool for working more effectively with complex data and maintaining situational awareness in demanding operational domains. Unfortunately, many applications of visualization technology fall short of expectations because the technology is used inappropriately - the wrong tool applied in the wrong way. A study of visualization techniques as applied to one particularly demanding area, information assurance, leads to the conclusion that there is a proper and formal way to approach designing visualization techniques for maintaining situational awareness in complex domains. Visualization techniques should be specifically designed or selected to align with one of the three identified stages of situational awareness - perception, comprehension, or projection -and with one of five standard uses of visualization - monitoring, inspecting, exploring, forecasting, or communicating. Greater value can be realized by selecting the right visualization technique to focus on each operational task, rather than searching for a single all-encompassing solution to fit every need. Examples of how visualizations can be used to support specific tasks of IA analysis are presented, with examples based on a review of available literature, a formal cognitive task analysis performed by the authors, and lessons learned from direct experience with developing IA visualizations and training analysts in their use.