1. A system for integrating Web Services with business systems, comprising: a processor; and a memory comprising program instructions, wherein the program instructions are executable by the processor to implement a Web Services architecture design service configured to generate integrated Web Service architectures for integrating Web Services with business systems, wherein, to generate an integrated Web Service architecture for integrating a specific Web Service with a specific business system, the program instructions are executable by the processor to: generate the integrated Web Service architecture comprising a plurality of heterogeneous components of the specific business system in accordance with one or more Web Services integration design patterns for integrating Web Services with business systems, wherein, to generate the integrated Web Service architecture, the program instructions are executable by the processor to: generate one or more Use Cases for the integrated Web Service in accordance with the one or more Web Services integration design patterns, wherein each Use Case models a particular business scenario for the integrated Web Service; generate a high-level architecture for the integrated Web Service in accordance with the one or more Web Services integration design patterns, wherein the high-level architecture identifies two or more entities of the integrated Web Service and the relationships and interactions among the entities; and generate a logical architecture for the integrated Web Service according to the business scenarios modeled by the one or more Use Cases and in accordance with the one or more Web Services integration design patterns, wherein the logical architecture identifies two or more logical components of the integrated Web Service and the relationship among the two or more logical components according to a plurality of integration tiers, and wherein the logical architecture comprises two or more layers; and provide output indicating the generated integrated Web Service architecture for integrating the specific Web Service with the specific business system.