Many approaches to work analysis have been proposed to enhance the requirements elicitation for systems design. However, systems delivered at dynamic, complex and socio-technical workplaces have still failed at satisfying the users’ real needs, mainly because they are unable to support users’ activities entirely, especially those related with cognition and collaboration aspects. We argue that the use of a combination cognitive and observation techniques can contribute to enhance the requirements elicitation activity, particularly if a collaborative approach is also adopted. This paper describes a collaborative observation model and a collaborative observation method aimed at improving the quality of the requirements elicitation process. We also include the description of a groupware prototype that supports our approach.