Math Affinity Puzzles highlights the patterns and relationships that appear throughout mathematics. Rather than treating mathematics as a collection of separate topics or isolated courses, the puzzles here look beyond boundaries to discover links among different areas of knowledge. The book uses analogies to explore connections between mathematical terms and concepts, where solving a puzzle requires unraveling the relationships between the mathematical ideas. Solving this kind of mathematical puzzle is thus not about assessing understanding, but deepening it, making the connections, and having fun doing it. Each puzzle is followed by a short description and further discussion, touching on the different choices while going more deeply into historical or other aspects of the relationships. In some cases, there may be multiple relationships present and the suggested answer is one of many. The puzzles in this book can be enjoyed on their own or as supplements in a course setting. The authors have used them in calculus and upper-level classes as homework assignments and for in-class discussions, offering opportunities for noncomputational critical thinking, speaking, and writing about mathematics. Regardless of their use, the puzzles will deepen the reader’s understanding and appreciation of the relationships among mathematical ideas.