This document is the preface to the second edition of the book "Smart Thinking: Skills for Critical Understanding and Writing" by Matthew Allen. It summarizes the purpose and revisions made for the new edition. The author found the first edition to be popular and useful for teaching critical thinking skills. For the second edition, he has made changes like providing more assistance in early chapters on complicated concepts and expanding later chapters on reasoning and research based on teaching experiences. The goal is to make the journey towards stronger critical thinking abilities easier for readers. Advice from teachers who used the first edition helped improve the new edition.