The Nine Windows tool provides an opportunity to look at a problem or issue through nine different lenses. This technique enables improvement teams to consider a wide range of opportunities for improvement. These nine windows reflect the intersections of time factors (past, present, future) and space factors (supersystem, system, subsystem). Developed by PHF Quality Improvement Experts Jack Moran and Sonja Armbruster, this tool is effective when an improvement team is having difficulty visualizing alternatives to the current state. Read the author's perspective on using this tool in Sonja Armbruster's PHF Pulse Blog post. See the full Nine Windows tool made available as a supplement to the Public Health Quality Improvement Encyclopedia.