Not knowing multiplication facts creates a gap in a student's mathematics development and undermines confidence and disposition toward further mathematical learning. Learning multiplication facts is a first step in proportional reasoning, "the capstone of elementary arithmetic and the gateway to higher mathematics" (NRC 2001, p. 242). Proportional reasoning, in turn, is central to success in money management, chemistry, physics, economics, and all phenomena involving change. In this article, the authors suggest an approach that aims to use and develop problem solving, reasoning, and confidence. Students are asked to identify what they know and to reason their way from using familiar facts to accumulating new ones. The process exploits the idea of "doubling," a natural and energizing process that many students already have mastered and which helps to initiate a learning strand that leads to proportional reasoning. Since learning multiplication facts is part of the elementary curriculum, a reasoning-based approach to fact fluency is not typically available in middle school. The authors would like to fill this gap and offer suggestions for use by classroom teachers, special education teachers, parents, and tutors. [A detailed table of problem sets with prompts and examples are appended to the online version of this article at www.nctm.org/mtms.] (Contains 3 figures.)