Enterprise 2.0 has been introduced in the SME (Small Medium Enterprise) modifying common organizational and operative practices. This brings the `knowledge workers' to change their working practices through the use of web 2.0 communication tools. Unfortunately, these tools do not allow intercepting and tracing the exchanged data, which can produce a loss of information. This is an important problem in an enterprise context because knowledge of the exchanged information can increase the efficiency and competitiveness of the company. In this article we demonstrate that it is possible to extract this knowledge by an abstraction process of the new operative practices, named collaboration processes, thanks to the use of design patterns. Therefore, we propose design patterns for the collaboration processes useful for modelling typical Enterprise 2.0 activities, having the goal of making more flexible and traceable the use of emerging operative practices.