1. A computer-implemented method for orchestrating a business process in an integration services network configured to mediate communication protocol and business policy differences among plurality of different services in communication with the integration services network, the method comprising: receiving, at a business process engine running on a server in the integration services network, a script describing a business process from a client machine in communication with the integration services network, wherein the business process described by the received script pertains to communicating with a subset of the plurality of different services; receiving, at the business process engine, a reference to the script and data to be operated on by the script from the client over the integration services network; retrieving, from a policy repository in the integration services network, communication protocol and message format information for the subset of the plurality of services; based on the reference to the script and on the retrieved communication protocol and message format information, invoking a first service of the subset of services from such script as a service request, including at least a portion of the data, the first service communicating with the integration services network using a first communication protocol; based on the reference to the script and on the retrieved communication protocol and message format information, invoking a second service of the subset of services from such script as a services request, including at least a portion of the data, the second service communicating with the integration services network using a second communication protocol that differs from the first communication protocol; determining a result of the business process at the business process engine, the result based on the invocation of the first and second services; and returning the result to the client machine.