Also known as chapter pedagogy or apparatus, this refers to how you will set up your chapters. You'll want to work out the following elements with your editor:
It can be jarring dealing with suggested changes. As authors, we work a chapter to our idea of perfection only to receive cryptic (or not so cryptic) comments on its flaws from another's view.
Is your true audience the faculty who will adopt your text or the students who will read it? I'd suggest that while you market to faculty you write for students.