This paper presents an initial evaluation of the syntactic-semantic component within a natural language spoken manmachine dialogue system, the SYNSEM component. After giving a brief account of the DIAL dialogue system, we present the validation methodology that aims at refining SYNSEM's underlying natural language models, and tuning the component's heuristic search strategies. Next we discuss the results of SYNSEM's validation obtained through several parses of a representative sample of utterances using various search strategies. Keywords: Natural Language Processing; Speech Processing; Syntactic Parsing; Assessment and Validation.