Hugely facilitated by the Internet, plagiarism by students threatens educational quality and professional ethics worldwide. Plagiarism reduces learning and is correlated with increased fraud and inefficiency on the job, thus lessening competitiveness and hampering development. In this context, the present research examines 48 licenciatura theses and 102 masters theses from five of Mozambique's largest universities. Of the 150 theses, 75% contained significant plagiarism (>100 word equivalents) and 39%, very much (>500 word equivalents). Significant plagiarism was detected in both licenciatura and masters theses. By using both Turnitin and Urkund to identify potentially plagiarized passages, professionally verifying whether those passages contain plagiarism, and, if confirmed, counting the words involved, the study presents a new method for classifying the quantity and significance of plagiarism. The use of two text-similarity-recognition programs also improved the rate of detection and, in some theses, significantly increased the classification of the gravity of the plagiarism encountered. Based on a broad review of the literature, the article argues that, to combat wide-scale plagiarism, academic institutions need to cultivate a consensus among faculty and students about the definition and types of plagiarism, the appropriate penalties, and the paramount professional and economic need to nurture professional ethics. However, to achieve even partial success requires significant involvement by administrators, faculty, students and student leaders guided by a holistic strategy using technological, pedagogical, administrative and legal components to prevent and detect plagiarism and then reeducate or discipline students caught plagiarizing.