Collaboration in the field of software development covers a wide range of team activities, from a co-located team working on a small project, to a geographically distributed project involving three or more time zones and hundreds of developers, some of them outsourced. This article describes <A HREF="http://www-128.ibm.com/developerworks/rational/library/apr07/pollice/index.html?ca=drs-">the current state of collaborative development</A> and considers several obstacles to optimum collaboration.