The quasi-experimental research study developed and tested an education process to reduce and trap medication errors. The study was framed by Endsley's (1995a) model of situation awareness in dynamic decision making. Situation awareness improvement strategies were practiced during high-fidelity clinical simulations. Harmful medication errors occur at distressing rates. Nurse educators are responsible for providing students sufficient experience needed to avoid preventable errors. Translocation of situation awareness training into nursing education for the purpose of promoting patient safety is a new approach. The 19 participants were attending either a nursing assistant or first semester nursing community college course. Participants were assigned to a series of two treatments and three evaluations in one of two counterbalanced repeated measures groups. Treatments emphasized practice simulations representing hospital medical-surgical environments. The three evaluations involved a simulation testing process. Four instruments were developed. Two instruments provided objective measures of performance demonstrated during video recorded testing simulations. Situation awareness was measured using scenario freeze queries based on Endsley's (2000) Situation Awareness Global Assessment Technique. The fourth instrument was a written debriefing form that included questions regarding self-confidence levels. Within participant main effects were significant for increased frequency of corrective interventions related to potential medication error factors F (2, 24) = 27.69, p less than 0.001; improved administration performance F (2, 24) = 25.26, p less than 0.001, and; increased situation awareness F (2, 24) = 31.47, p less than 0.001. Participant gain scores were consistent with learning curve patterns. Within participant interactions and between participant effects related to group or demographic factors (nursing course, campus, prior experience with simulation, ethnicity, or age) were insignificant for all measurements. Participant responses to debriefing questions demonstrated gains in self-confidence. Further research is needed to explore relationships between error trapping, medication administration procedures, situation awareness and decision making, and patient safety in a variety of simulated clinical environments. Study results demonstrated that well constructed problem solving based simulations designed for evaluating performance can serve as powerful information retrieval and learning reinforcement events. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]