The purpose of this study was to investigate the effects of two types of maps (generative vs. completed) and the amount of prior knowledge (high vs. low) on well-structured and ill-structured problem-solving performance. Forty-four undergraduates who were registered in an introductory instructional technology course participated in the study. Participants were randomly assigned to two treatments that used generative and completed concept maps. Within those treatment groups, participants were differentiated by prior domain knowledge, high or low. Although the high knowledge-generative group outperformed the other three groups on well-structured problem-solving performance, it did not have an effect on ill-structured problem-solving performance.