  The paper discusses how compositional semantics is implemented in the
Verbmobil speech-to-speech translation system using LUD, a description language
for underspecified discourse representation structures. The description
language and its formal interpretation in DRT are described as well as its
implementation together with the architecture of the system's entire
syntactic-semantic processing module. We show that a linguistically sound
theory and formalism can be properly implemented in a system with (near)
real-time requirements.
