Quantitative Reasoning for Professionals is a two-semester general education sequence that teaches basic and intermediate algebra through the lens of quantitative reasoning. In this course sequence, we emphasize communication and inference-making while teaching practical algebra skills for students in programs such as business, nursing, and social work. Students placing into this course sequence are statistically at-risk to drop out of college, and our experience indicates that lacking college-readiness skills are a primary factor in this risk. We created a mastery grading system that was specifically designed to promote skills and habits of mind that are associated with retention. With a view toward our pre-professional student audience, we framed these outcomes in the context of a "professional mindset." In this paper, we present the specifics of the professional mindset outcome and the context that led to its definition. We describe the specifics of our grading system and informally report on its failures and successes in promoting a professional mindset in our students.