The Lingua-AlignmentSet distribution is a Perl Tools Library (and command-line utilities) to handle an Alignment Set, i.e. a set of sentences aligned at the word (or phrase) level. It provides methods to display the links, to apply a function to each alignment of the set, to evaluate the alignments against a reference, and more. One of the objectives of the module is to allow the user to perform all these operations without bothering with the particular physical format of the Alignment Set. Anyway it also provides format conversion methods.