This research study was performed in an attempt to fill an apparent void regarding the relative utility and comprehensiveness of three published, theoretically-based, idiographic, initial assessment inventories: Integral Intake (II), Life-Style Introductory Interview (LI), and Multimodal Life History Inventory (MI). “Experts” -- defined as professors of counseling or psychology and licensed practitioners who have been practicing as counselors or psychologists for at least five years - read through the inventories and then evaluated them by responding to both (qualitative) open-ended questions as well (quantitative) rankings and ratings. The researcher posed three primary research questions: 1) how do participants' evaluations differ regarding the overall helpfulness of the three inventories; 2) how do participants' evaluations differ regarding the comprehensiveness -- both relative to each of the eight dimensions of the client (thoughts, emotions, behaviors, physical aspects of the client, physical aspects of the client's environment, culture, spirituality, and what is most meaningful to the client) and overall -- of the three inventories; and 3) how do participants' evaluations differ regarding the efficiency with which the three inventories assessed the eight dimensions. Results indicated that participants consistently evaluated the II and MI as more helpful, comprehensive, and efficient than the LI - both overall and relative to the eight specific dimensions. The LI was consistently evaluated as the worst of the three inventories -- on all dimensions. The MI was evaluated as the best inventory on four dimensions: the client's thoughts, emotions, behaviors, and physical aspects. The II was evaluated as the best inventory on seven dimensions: physical aspects of the client's environment, client's culture, client's spirituality, what is most meaningful to the client, and, notably, on overall comprehensiveness, overall efficiency, and overall helpfulness. Another goal of this research was to obtain feedback from the participants relative to how to improve the II. This goal was also accomplished and the researcher will implement this feedback into subsequent versions of the Integral Intake.