Client-centered, outcomes-based mental health counseling is driving the behavioral health field toward identifying mechanisms to facilitate specific, measurable goal setting and tracking with clients. Motivational interviewing (MI) is an evidence-based, collaborative, goal-oriented style of counseling; however, the fourth process of MI, planning, is not as well defined as the other MI processes, especially related to goal setting. Goal attainment scaling (GAS) is a method for setting measurable goals and assessing clinical progress. The combination of MI and GAS has potential to be a valuable clinical tool to establish client-centered goals, monitor goal attainment, and provide feedback within clinical mental health settings. Therefore, we propose that the MI planning process can be enhanced by incorporating GAS. However, research is needed to substantiate the feasibility of the proposed integration. A brief case study is provided to illustrate key concepts.