One important tendency in software development has been the globalization of its industry. Software developers are frequently required to work in groups which are distributed throughout multiple geographic locations. People and processes (e.g. software design) are consequently distributed. Providing the support that will allow distributed software developers to collaborate at a convenient moment, is therefore extremely complicated both for the person making contact and the person being contacted. We therefore propose a characterization and a model of Collaborative Working Spheres (CWS) through which to understand the management of activities in distributed software development (DSD). Our work first aims to characterize DSD activities mainly through a survey of literature. We then describe a projected scenario to illustrate how DSD activities can be supported by technology and finally we propose a characterization of CWS through which to represent how DSD workers can collaborate at a moment which is suitable for all involved participants.