Treatment planning and monitoring are essential components of mental health service delivery in the era of managed care. Personality assessment instruments have long been used by practitioners to assist in psychodiagnosis and the identification of treatment needs and goals. Nevertheless, managedcare companies and 3rd-party payers are reluctant to authorize psychological assessment service and, instead, prefer that clinicians base their plans on clinical interviews. Research is reviewed documenting the utility of personality assessment instruments in empirically guided treatment planning and the superiority of this method over clinical interviewing. A new psychological test designed specifically for use in treatment planning, the Butcher Treatment Planning Inventory (J. N. Butcher, in press), is introduced and described.Treatment planning and monitoring are essential components of mental health service delivery in the era of managed care. Personality assessment instruments have long been used by psychologists to assist in psychodiagnosis and the identification of treatment needs and goals. It would, therefore, be reasonable to expect that psychological assessment would play a significant and increasing role in current approaches to mental health treatment delivery. However, as readers of this journal are well aware, psychological assessment, instead, is more often viewed as a candidate for elimination or substantial cutback in the interest of cost-containment.Griffith (in press) reported results of a recent survey of nine large managed-care firms. The prevailing view among these companies was that assessment in general and comprehensive psychological test batteries in particular are not cost-effective tools for psychodiagnosis and treatment planning. Griffith's survey results indicate that managed-care companies view interviews as a cost-efficient and preferred alternative to psychological assessment.Consistent with the views reflected in Griffith's (in press) survey, third-party insurers and managed-care companies are reluctant to reimburse psychologists for assessment services. Practitioners, in turn, conduct fewer psychological assessments. Consequently, although clinicians are required to specify goals for intervention and develop plans for meeting these goals, often treatment needs are identified on the basis of nonstandardized clinical interviews. Practitioners then turn to payment authorizers for approval of their plans and find themselves ill-equipped to present evidence in support of their opinions when they are (not uncommonly) challenged. Butcher (1997) suggested that in the era of accountability, imposed on the mental health field by third-party payers and