Carl Rogers went through several phases in his approach to counseling. His first, which seems to follow the maxim "First, do no harm" (the Hippocratic Oath), was "Client-Centered Therapy" in which the counselor primarily listened to the client and "fed back" what the client said in other words, thus helping the client to work through and solve his/her own problem.
Rogers' approach was the basic one we learned at my theological school, to help us with our eventual pastotral counseling. (The graduate program was entirely Jungian, however.) The basic idea was that with Rogers' counseling approach, we would at least not CAUSE more problems for our clients!
(It would not be for several decades that I'd find out that Adler's approach was the first basis for pastoral counseling, despite that Jung was an avowed Swiss Protestant. Adler's approach was and is recommended to clergy (Protestant, Catholic, Jewish, liberal, conservative, and evangelicals) as the best basis for pastoral counseling.)
Rogers became ingterested in the "encounter" movement of the late 60s/early 70s. His approach was organized around what became known as "active listening," in which the group leader as well as the participants reflectedd comments "in other words" and emphasized (which were treated as "facts" or "data") rather than behaviors, past causes, etc.
Throughout, Rogers approach was "humanistic" (person-centered) and "phenomenological" (focusing on subjective belief rather than objective "fact." Very close to the end of his life, Rogers wrote how much he had been influenced in his thinking when he was a student of Dr. Alfred Adler while studying in Chicago. Indeed, a number of famous psychologists were among his students, such as: Erich Fromm, Abraham Maslow, Rollo May, Karen Horney, Julian Rotter (Univ. of CT, one of my grad schools!), E. C. Tolman, and of course, Carl Rogers.
For more on Adler: http://www.lifecourseinstitute.com
For more on Rogers: http://webspace.ship.edu/cgboer/rogers.html