Abstract: Service orientation promotes the construction of network-based applications in a loosely-coupled manner.Some new challenges are brought forward in handling exceptions.In this paper, exceptions raised during the construction and execution of service-oriented applications are analyzed, with emphasis on the exceptions related with the unavailability of services.An exception handling approach is presented.The approach has been used in a project that is targeted for the Olympic Games 2008 and mediates individual services for the general public.