The short- and long-term success of posterior composites depends on both the singer and the song: very careful attention to detail and a logical, evidence-based selection of materials. Most of us will agree that a class II composite is significantly more technique sensitive than a class II amalgam, and that the selection of materials (and equipment) can be confusing and frustrating. The instructor will take a hard look at the state of the class II composite in 2023 and will address questions like: Is composite always a better alternative to amalgam? Why should we practice minimally invasive dentistry? What about extension for prevention? Which generation of bonding agents should we use? What is the best matrix, and why? Why, and how, should flowable composites be used? What about bulk-fill materials? Is incremental curing still the gold standard? What is the best curing light?