This library section contains an implementation of several modern methods for cluster analysis as described in the book "Finding Groups in Data: An Introduction to Cluster Analysis" by L. Kaufman and P. J. Rousseeuw (1990). The methods, (daisy, pam, clara, fanny, agnes, diana and mona), are described in the help files and in the chapter "Cluster Analysis" of the S-PLUS documentation. The S-PLUS implementation was developed by Mia Hubert, Peter Rousseeuw and Anja Struyf at the Department of Mathematics and Computer Science, Universitaire Instelling Antwerpen (University of Antwerp).