Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for reducing redirects. In one aspect, a method includes receiving request data indicating that a user device has requested a content item. The request data specifies other data processing apparatus to which user interactions with the content item are to be reported. The content item includes a reference to a resource that is requested in response to user interaction with the content item. Response data is provided. The response data includes data that cause presentation of the content item. Interaction data is received specifying user interaction with the content item occurred. Redirect data is provided that cause the user device to be redirected to the resource. Reporting data is provided to the other data processing apparatus, specifying user interaction with the content item occurred. The reporting data is provided asynchronously relative to the redirect data.