Abstract. There is an increasing need for practical and comprehensive evaluation methods and tools for conformance testing with ISO standards.In this study, we focus on ISO9241 which is an important ergonomic standard. A brief description shows its content and structure. Practical evaluations include the amount of time and resources which must be managed in software projects,while comprehensive evaluations require that the context of use be considered during the evaluation of user interfaces. In order to complete a comprehensive evaluation of usability, it is necessary to use more than one evaluation method. Therefore, an overview of different evaluation approaches is given, describing their advantages and disadvantages. Finally, the ISO 9241 evaluator is presented in detail as an example of a practical expert-based evaluation method for conformance testing with the ISO 9241 standard, that can be integrated in a comprehensive evaluation approach.