Computational aspects of geometry of numbers have been revolutionized by the Lenstra Lenstra Lovasz lattice reduction algorithm (LLL), which has led to bre- throughs in elds as diverse as computer algebra, cryptology, and algorithmic number theory. After its publication in 1982, LLL was immediately recognized as one of the most important algorithmic achievements of the twentieth century, because of its broad applicability and apparent simplicity. Its popularity has kept growing since, as testi ed by the hundreds of citations of the original article, and the ever more frequent use of LLL as a...