In our last episode, we established the foundations of anal cancer therapy, proving that definitive chemoradiation with 5-FU and Mitomycin-C is the organ-preserving standard of care. But while this approach is highly effective, it is also notoriously toxic. The older 3D radiation techniques often led to severe side effects and treatment breaks that compromised outcomes.Today, we focus on the modern "how." We'll explore how IMRT has revolutionized our ability to treat this disease. We'll walk through a detailed, dose-painted IMRT planning workshop. And finally, we'll use a case to discuss the management of special populations you will frequently encounter: HIV-positive patients, those with high-risk disease, and those with recurrence.