Integration testing allows you to test the interactions between different components of your Web API and external dependencies. In ASP.NET Core Web API, you can implement integration testing using frameworks like xUnit, NUnit, or MSTest, along with tools like Microsoft.AspNetCore.TestHost. The TestServer class provided by TestHost allows you to host and make requests to your API in a test environment. Integration tests can cover scenarios such as API endpoints, authentication and authorization, database interactions, and external API integrations. By executing integration tests, you can validate the overall behavior and correctness of your Web API.