The concept of Web services is believed to propel what are called "services-driven enterprise architectures." What it means is that every computing resource in the enterprise will be converted or conceived as a service, and every other application that needs this service will be using it over and over again.
For example, let's consider a banking scenario.
In present architectures, every application that needs to access the customer details will either query the database directly or access the resource through adapters, messaging systems, and many other means. The point to note here is that every application may adopt its own methodology to achieve the same objective: accessing the customer details.
But in a service-driven enterprise, access to customer details can be published as a Web service in an enterprise directory system, thus making it available across the enterprise network. Any application can make use of this service, as long as it is able to send and consume SOAP messages across the network.