This chapter encourages each clinician to become their own local clinical scientist (Stricker & Trierweiler, 1995) by establishing a results-based accountability model that produces evidence-supported practices. Evidence-supported practice is established from the combination of a treatment approach or intervention (with a rationale to explain why clinical change is expected), a grounding in research literature on the presenting problem(s) and population in treatment, and an assessment of the outcome of treatment (how well does the treatment work). Whereas the chapters that follow focus on the treatment intervention and research literature, this chapter addresses outcome assessment. To best demonstrate the assessment process, this chapter describes a method by which therapists can implement outcome assessment, referred to as results based accountability (RBA;Friedman, 2005), and introduces a new outcome instrument (the Genogram-Based Interactional Measure [GBIM]), currently being field-tested, that measures interpersonal changes during treatment.