The problems of integrating information and processes between businesses continue to represent a challenge for which no universal solution has been found. Service Oriented Architecture (SOA) represents a technology leap in this direction, allowing businesses to define the functionality of their various systems as discrete, loosely coupled services, accessible through well defined interfaces. Augmenting the SOA approach with Semantics guarantees unambiguous Web Service descriptions and explicit meaning for the data they interchange. We describe an example to motivate semantic enhancement and present WSMX as a semantic execution environment addressing the search and integration challenges. We propose that using WSMX, complex collaboration scenarios can be built in a dynamic fashion, sustained by concrete solutions that solve heterogeneity issues at the data, process and protocol levels.