The unification grammars defined by the user in a PATR like style are compiled into Prolog (an extension to the compilation described in ), to enable an efficient implementation of parsing, generation and transfer. The parser is a `left-corner' parser augmented with a well formed substring table and a reachability table . Both techniques are optimized by using a set of `restricted' features . The generator of Mimo2 is a member of the generation family described in . Transfer is implemented as a top-down backtrack search procedure.