Out-of-process hit-testing can provide increased privacy and efficiency in computer user input systems. In an aspect, an application specifies a control style for a UI window to be managed separately from the application, such as by a system process running outside of the application process. When a user input is received at a location corresponding to a part of the application UI that is separate from the UI window for which the control style has been specified, the user input may be redirected to the UI window for which the control style has been specified.