Paperfolders at every level of expertise will appreciate this original compilation of models inspired by mathematical principles. Origami master John Montroll presents 39 projects, each made from a single square sheet of paper. Models range from the simplicity of a triangle to highly complex cubicles and other geometric shapes. Montroll, who is noted for meticulously developed folding sequences that result in better models with fewer steps, provides detailed instructions and diagrams. He also discusses techniques for dividing paper into fractions, folding to any location on the edge of the square, and using mathematics to attain precision in folding animal models, including camels and elephants. Other models include a collection of polygons, 2-D and 3-D models that employ pentagonal symmetry, and eight chessboards of increasing complexity.