We present an approach for the validation and verification of Web Services choreographies,

and more specifically, for those composite Web Services systems with

timing restrictions. We use a W3C proposal for the description of composite Web

Services, WS-CDL (Web Services Choreography Description Language), and we define

an operational semantics for a relevant subset of it. We then define a translation

of the considered subset ofWS-CDL into a network of timed automata, proving that

this translation is correct. Finally, we use the UPPAAL tool for the validation and

verification of the described system, by using the generated timed automata.