A model is a simplified representation of the real world. Engineers use models to gain confidence in the adequacy and validity of a proposed design. Models are described using state machines, known as Labelled Transition Systems (LTS). These are described textually as Finite State Processes (FSP) and displayed and analysed by the LTSA analysis tool. This package provides the LTSA utility exposed above. It is specially useful to be used together with the 'Concurrency: State Models & Java Programs' book, whose page is at http://www-dse.doc.ic.ac.uk/concurrency/.