Much of the recent growth in outsourced application services has been fueled by customers engaging independent testing services where the development provider is separate from the provider performing the testing. This approach addresses the inherent conflict of interest between development and testing activities, ensuring appropriate rigor in the testing process. However, engaging with a separate supplier for testing in addition to engaging for outsourced development or maintenance will present challenges, including those endemic to managing multiple vendors in general. Customers must maintain effective segregation of development and testing tasks while maintaining visibility and unified governance, as far as their existing organizational structure and sourcing maturity allow.