Gerald R. Weeks 
Treating Couples [PDF ebook] 
The Intersystem Model Of The Marriage Council Of Philadelphia

In some ways the development of the theory and practice of marital therapy seems like a relative newcomer to those clinicians who practice systems therapy. Most of the books in the field stress the total family as the unit of treatment in terms of understanding the dynamics of family interactions and intervention techniques. For the past 15 or 20 years, clinicians interested in systems work sought training in "family" therapy programs and at "family" therapy workshops. This training led to a dramatic shift in the practice of psychotherapy away from the individual as the unfit of treatment to the family. Much less emphasis has been given to the marital dyad or couple as the unit of treatment.