In the tradition of Sherlock Holmes, Dr. Ecco is one of the greatest sleuths of our time, a mathematical wizard who uses logic and computer programming to solve crimes, find treasures, and explore space. Join his team, expand the frontiers of your knowledge, and match wits with him on intriguing cases like The Virus from the Spy and The Secrets of Space and The Caribou and the Gas. The puzzles collected here require no formal background beyond arithmetic and elementary algebra-just lively curiosity and keen intelligence. With thirty-six illustrated cases organized around eight major mathematical themes (from Combinatorial Geometry and Geography to Ciphers and Secrecy) this book will encourage you to use your mind and your computer in ways you never previously imagined.