Internal Family Systems (IFS) therapy is a synthesis of two paradigms: the plural mind, or the idea that we all contain many different parts, and systems thinking. With the view that intrapsychic processes constitute a system, IFS invites therapists to relate to every level of the human system -- the intrapsychic, familial, communal, cultural, and social -- with ecologically sensitive concepts and methods that focus on understanding and respecting the network of relationships among members. IFS therapy is also collaborative and enjoyable. And because we view people as having all the resources they need rather than having deficits or a disease, it is nonpathologizing. Instead of seeing people as lacking resources, we assume people are constrained from using their innate strengths by polarized relationships, both within and with the people around them. IFS is designed to help us release our constraints and, in so doing, also release our resources.

— Internal Family Systems Therapy by Richard C. Schwartz, Martha Sweezy (Page 5)