Problem solving is a key component of authentic scientific research and practice in organic chemistry. One factor that has been shown to have a major role in successful problem solving in a variety of disciplines is metacognitive regulation, defined as the control of one's thought processes through the use of planning, monitoring, and evaluation strategies. Despite the growing interest in assessing and promoting metacognition in the field of chemical education, few studies have investigated this topic in the context of organic chemistry students. To gain a deeper understanding of how and why students make use of strategies related to metacognitive regulation in their approaches to solving problems, we conducted interviews with Organic Chemistry I, Organic Chemistry II, and graduate organic chemistry students and used multiple measures to examine students' metacognition. As a part of these interviews, students verbalized their thoughts as they worked on complex predict-the-product problems and completed a self-report instrument indicating which planning, monitoring, and evaluation strategies they had used while completing each problem. Think-aloud protocols were analyzed for the presence of each of the behaviors included on the self-report instrument, and students' use of metacognitive strategies was compared to identify differences between students with different levels of experience and between students who generated more and less successful solutions to the problems. Students who generated more successful solutions to the problems tended to report using a greater number of metacognitive strategies. When asked why they did or did not use certain metacognitive strategies, students indicated a number of factors, such as not feeling able to use these strategies effectively or believing that using these strategies was unnecessary. The results of this study support the importance of teaching metacognitive problem-solving strategies in organic chemistry courses and suggest several methods for the assessment and instruction of metacognition.