Very few formal studies have documented the errors committed in online searching performances, and none have focused exclusively on students in library and information science programs. To fill this gap, the authors conducted a content analysis of online searching errors of MLIS students based upon a coding scheme derived from previous error typologies and enhanced with new categories related to strategic searching decisions. The results suggest that errors committed by MLIS students align with errors identified in previous online searching studies but also include errors that seem unique to the MLIS participants' searching outcomes. Using observed error patterns, the authors suggest instructional activities that can be developed to teach techniques for error correction and avoiding tactical and strategic flaws in online searching assignments.