Lexicalized Tree Adjoining Grammars have proved useful for NLP. However, numerous redundancy problems face LTAGs developers, as highlighted by Vijay-Shanker and Schabes (92). We present and a tool that automatically generates the tree families of an LTAG. It starts from a compact hierarchical organization of syntactic descriptions that is linguistically motivated and carries out all the relevant combinations of linguistic phenomena. 1 Lexicalized TAGs Lexicalized Tree Adjoining Grammar (LTAG) is a formalism integrating lexicon and grammar (Joshi, 87; Schabes et al., 88), which has proved useful for NLP. Linguists have developed over the years sizeable LTAG grammars, especially for English (XTAG group, 95) and French (Abeill6, 91). In this formalism, the lexical items are associated with elementary trees representing their maximal projection. Features structures are associated with the trees, that are combined with substitution and adjunction. Adjunction allows the extended domain of l...