In User-centered design and participatory approaches, the requirements analysis and the evaluation of proposals and solutions are essential. Many methods can be used at different times in projects. It is possible to use them in the early stages, when the vision of the system is not yet clear; it may then be necessary to encourage and support ideation. Different types of methods can also be used on the basis of diagrams, mockups or prototypes. This can be the case for example in iterative approaches and agile projects. In addition, at the beginning of a project, it is possible to study one or more existing systems: this study will serve as a support for the analysis of the needs to move towards a new system or a new version. At the end of the project, the product can be evaluated in a usability (or UX) lab and/or in real contexts, before being used internally or marketed. There are therefore many situations requiring the use of various methods. The keynote will give an overview of the main categories of methods. More and more projects require the involvement of people with disabilities. A categorization of disabilities will be presented. The characteristics and needs of the people involved may require an adaptation of the methods used for requirements analysis and evaluation of interactive systems. The presentation will provide illustrations from different projects with various disabilities.