The need to understand the social context within which work to be supported by computer-based systems takes place is broadly recognised within the RE community. Ethnographic studies have been used in particular to inform the requirements process from a social perspective. To make this accessible to requirements engineers, work in this area has focused on how to integrate and communicate ethnographic findings on a per project basis but scant attention has been paid to how findings from individual studies may be generalised and re-used for the purposes of RE in new settings. This paper is intended to introduce our resource of Patterns of Cooperative Interaction to the RE community. These patterns specifically compare and contrast a variety of ethnographic findings, discuss their relevance to design and provide an introduction to the analytic sensibilities of such studies. We discuss how we developed patterns of interaction from a corpus of ethnographic studies, illustrate a selection of these patterns and suggest how the patterns collection can be used by requirements engineers as a means of highlighting potential social issues that are relevant to the system requirements and as a means of generating requirements that support social interaction.