Abstract : In a professional environment characterized by its complexity and its evolution, softwaredesigners face the difficulties of having to propose innovative, reliable and durabletechnological solutions, despite a lack of steady systems of reference. In this context, socialconfigurations that remain transversal to firms (e.g. professional networks) have appeared,and henceforth represent new kinds of references for computer engineers. A comparativeanalysis of four specific environments of computer design underlines the multiplicity of thecontribution of these social configurations. Indeed, they support the operational activity,enabling to open up resources, skills and knowledge, and to improve collective learning.Moreover, inscribing a computer work is these social configurations reinforce a recentprofessional activity that lacks of deep collective references. Gratitude and acknowledgmentby peers are based on the practice of an art, and are emancipated from constraints thatremain external to technology. Relationships between members of these non formalcommunities are the basis of identity demands preliminary to the constitution of aninstituted profession. Furthermore, the role of these new social configurations questionsabout the evolution of the professional environment, which the network is a real andspecific configuration in. Especially, the informal character of exchanges shows thecontemporary importance of gift and free transactions, even in highly commercialenvironments.