Worden gives a detailed report of analytic work with a 'borderline' patient, illustrating in particular the problems of interpretation when little observing ego is present. His preliminary discussion is thought-provoking; it relates to the problem of introducing parameters into the classical analytic procedure while working with patients with defective ego functioning. The young woman patient was extremely difficult to treat. Because of the chaotic and stormy course of her life and of the analysis, Worden, finding his interpretations ineffective, used various parameters. When he was finally able to aim his interpretations so that they facilitated and supported her ego's capacity to observe and collaborate analytically at the level of secondary process thinking, there was a dramatic change in the course of her analysis and life. Her erratic behavior and lack of reality testing were found to operate as defenses against intense guilt which she had to avoid feeling and knowing about. Worden then directed his interpretations systematically to this defensive activity. He believes that he assisted her in