This report describes two applications of a multivariate method for studying classes of nucleotide or protein sequences: correspondence discriminant analysis (CDA). The first example is the discrimination between Escherichia coli proteins according to their subcellular location (membrane, cytoplasm and periplasm). The high resolution of the method made it possible to predict the subcellular location of E.coli proteins for whom this information is not known. The second example is discrimination between the coding sequences of leading and lagging strands in four bacteria: Mycoplasma genitalium, Haemophilus influenzae, E.coli and Bacillus subtilis. The programs used for computing the analysis are integrated in a publicly available package that runs on MacOS 7.x or Windows 95 operating systems (http:/(/)biomserv.univ-lyonl.fr/ADE-4.html). These programs are also accessible through our World Wide Web server (http:/(/)biomserv.univ-lyonl.fr/Net Mul.html).