This is Episode 17b: Definitive Planning Workshop Simulation, Target Volumes, and OAR Constraints. In Episode 17, we covered the clinical decision-making for definitive chemoradiation—why we treat, who needs systemic therapy, and which agent to use. Now we're at the contouring workstation, and we need to answer the technical questions: *How* do we treat? This episode is high-yield for both written and oral boards. Examiners love to probe your understanding of target volume delineation, nodal coverage algorithms, and constraint trade-offs. They'll ask why you included or excluded specific nodal levels, how you balance tumor control against late toxicity, and what happens when your plan can't meet all constraints simultaneously. We're going to work through our case patient step by step—from simulation setup through plan evaluation. By the end, you'll have a systematic framework for definitive oropharyngeal cancer planning that you can defend on boards.