A method and apparatus for providing on-demand computer diagnostics are provided. A control object is retrieved and stored at a client computer that is operative to retrieve a diagnostics module in response to a user request. The control object is also operative to receive a request from a user to execute the diagnostics module and, in response to the request, to determine whether execution of the diagnostics module is authorized. If execution is authorized, the control object is further operational to execute the diagnostics module to perform the requested diagnostic. The diagnostics module may be configured to only execute in response to commands issued by the control object. The control object may also be operative to authorize retrieval and execution of the diagnostics module through communications with a diagnostics server computer.