TestNG is a test framework which is designed to cover all categories of tests: unit, functional, end-to-end, integration, (etc). It includes a lot of features such as flexible test configuration, support for data-driven testing (with @DataProvider), powerful execution model (no more TestSuite) (etc). Spring testing support covers very useful and important features for unit and integration testing of spring based applications. The org.springframework.test.context.testng package provides support classes for TestNG based test cases. This article shows how to test Spring Service layer components by using Spring and TestNG integration. Also next article will show how to test Spring Data Access layer components by using same integration.