Algorithm Engineering and Experimentation : International Workshop ALENEX’99 Baltimore MD USA January 15–16 1999 Selected Papers This book constitutes the thoroughly refereed post workshop proceedings of the International Workshop on Algorithmic Engineering and Experimentation ALENEX99 held in Baltimore Maryland USA in January 1999.The 20 revised full papers presented were carefully selected from a total of 42 submissions during two rounds of reviewing and improvement. The papers are organized in sections on combinatorial algorithms computational geometry software and applications algorithms for NP hard problems and data structures