LT TTT, a recently developed software system which provides tools to perform text tokenisation and mark-up. The system
includes ready-made components to segment text into paragraphs, sentences, words and other kinds of token but, crucially, it also allows
users to tailor rule-sets to produce mark-up appropriate for particular applications. We present three case studies of our use of LT TTT:
named-entity recognition (MUC-7), citation recognition and mark-up and the preparation of a corpus in the medical domain.