This chapter focuses on group outcome and assessment research with a specific emphasis on an Evidence-Based Practice (EBP) approach, using as examples the Outcome Questionnaire-45.2 (OQ) and the Group Questionnaire (GQ). Vignettes will illustrate the advantages and implementation of these clinical assessments. They will demonstrate how using this particular EBP approach provides real-time feedback to group leaders for group process variables of Positive Bond, Positive Work, and Negative Relationship. These process variables can be viewed in relation to member-to-member, member-to-group, and member-to-leader interactions. Further discussion of how such research-based assessments facilitate better outcomes for group members will be explored.