The Agency for Healthcare Research and Quality (AHRQ) funds research leading to patient safety improvements in all settings and systems of care delivery. While many researchers have endorsed a systems model as a way of thinking about entrenched patient safety problems, there has been a scarcity of programmatic activity that actually engages in new design and systems engineering effort, and that is focused on more than singular patient safety concerns. This P30 FOA calls for the creation and utilization of Patient Safety Learning Laboratories. These learning laboratories are places and professional networks where closely related threats to patient safety can be identified, where multidisciplinary teams generate new ways of thinking with respect to the threats, and where environments are established conducive to brainstorming and rapid prototyping techniques that stimulate further thinking. Learning laboratories further enable multiple develop-test-revise iterations of promising design features and subsystems of the sort that can be found in larger-scale engineering projects. Once the closely aligned projects or subsystems are developed, integrated, and implemented as an overall working system, the ultimate function of the learning laboratory is to evaluate the system in a realistic simulated or clinical setting with its full complement of facility design, equipment, people (patients, family members, and providers), new procedures and workflow, and organizational contextual features, as appropriate. Applicants will select two to four closely related projects that focus on well-known, costly, patient safety harms in a given clinical area, and for which new and innovative design approaches are needed. While applicants will select the area of patient safety focus they consider of high significance, a flexible methodology problem analysis, design, development, implementation, and evaluation is provided that parallels the system development process to give an underlying structure to the four-year level of effort.