Kakuro 1: Beyond Sudoku - The Ultimate Cross Sums Challenge

Millions have succumbed to the phenomenon of Suduko, and it has spawned thousands of books, websites and daily puzzles in a number of national newspapers throughout the world. Yet in Japan, home of Sudoku, Kakro, or Kakuro is a far bigger phenomenon, appearing in over 70 different magazines and newspapers with over one million Kakuro books sold to date.