For most people, sex and sexuality are an important piece of their intimate (and sometimes, non-intimate) relationships. By the time a couple comes to therapy, it's not unusual to hear something along the lines of "we're just room-mates" or "what happened to our sex life?" While relationship conflict can have a severe impact on a couple's sex life, it's not unusual for a lack of recent knowledge about sex to be a factor, as well.
In Come As You Are, sex educator Emily Nagoski does a great job of explaining recent learnings about sex and desire. For example, one can think of desire as a combination of an accelerator and a set of brakes. Some of us have strong accelerators, some of us have strong brakes, some have strong accelerators and brakes, and others have weak accelerators and brakes. Learning that we are all different and what impacts our accelerator and brakes, as well as those of our partner can make a huge difference in understanding what can get in the way of (or lead toward) great sex (or any sex).