Teaching is a messy profession, the details of teachers' work are tightly woven into the myriad ways of humans. Even with uncertainty, teachers do improve their practice. In this article, the author describes how she moved her thinking forward over 35 years as an increasingly experienced teacher. Like many CES teachers, the ways that she has increased her knowledge, or learned new things, have come through a wide array of sources, some of which have been book- or research-based, and some of which have been through formal professional development. At the same time, a lot of her growth, especially once she settled in at Fenway High School, came through conversations with others, watching their head of school or another teacher taking risks and analyzing with them afterward. All of them trying to make really good, informed guesses. They are watching for good results, and then figuring out and sharing with others through talk why their efforts did or didn't work. The author contends that good teaching is a conversation; it is always at least a duet. With students, the conversation works or doesn't work depending on the myriad and mysterious ways that teachers build trust across age, gender, ethnicity and personality. With colleagues, knowledge that influences practice grows as teachers share it and "work it" with each other. Good talk is difficult but it makes teachers' work more powerful, satisfying, fun, and beautiful.