Frank Longo is a freelance puzzle creator living in Hoboken, NJ. While he has had over 3,000 crossword puzzles published since 1993, he has focused on the sudoku craze for the past several years. He has published nearly 100 sudoku books, with a wide variety of Puzzlewright titles such as Supersized Book of Sudoku; Beyond Black Belt Sudoku; 10x10 Sudoku; Mensa Absolutely Nasty Sudoku Level 1, 2, 3, and 4; The World's Longest Sudoku Puzzle; Poolside Sudoku; and Puzzlewright Guide to Solving Sudoku (coauthored with Peter Gordon). He is known for producing puzzles that are diabolically difficult yet fair, requiring the solver to use advanced techniques not found in typical newspaper and magazine sudoku puzzles.