The modern workplace is inherently collaborative, and this collaboration relies on effective communication among co-workers. Many communication tools – email, blogs, wikis, Twitter, etc. – have become increasingly available and accepted in workplace communications. In this paper, we report on a study of communications technologies used over a one year period in a small US corporation. We found that participants used a large number of communication tools for different purposes, and that the introduction of new tools did not impact significantly the use of previously-adopted technologies. Further, we identified distinct classes of users based on patterns of tool use. This work has implications for the design of technology in the evolving ecology of communication tools.