While plagiarism cases are on the rise since the advent of generative artificial intelligence (GenAI), higher education institutions must determine how they will deal with this new reality. This chapter explores how to prevent plagiarism when GenAI is used in academic writing. The Academic Integrity Crossway model puts prevention at the heart of a combined approach of surveillance and guidance where students’ written assignments are channeled through prevention. Surveillance—in the form of plagiarism detection or sanctions—is needed to deter academic misconduct while guidance—in the form of pedagogical methods and interventions such as restorative practices—is needed to foster academic integrity. Our model furthers this coalition by adding AI to contribute to every part of the prevention process. On the one hand, AI can assist institutions for surveillance purposes with detection and management tools, uncovering plagiarism cases and improving how they are handled. On the other hand, AI can provide guidance by serving as academic integrity tutors to students while they are writing as well as their academic integrity mentors after they’ve been caught plagiarizing. Our model shows that plagiarism prevention and academic integrity promotion are complementary as positive actions made by humans and GenAI are best suited to achieve a flourishing culture of academic integrity.