There's remarkably little data available on this question. It appears that the average length of time for a telecommuting assignment is between six and eighteen months; after that time, something usually happens to bring the person back to the office. However, there are many telecommuters who have been doing it for several years and are likely to continue. Others will do it sporadically - working at home a few days a week for a period of time, then going back to the office full-time, then back to telecommuting. The key is to remember that the best telecommuting is flexible telecommuting - in which we allow and encourage people to work where they work best depending on their personal style, the nature of the work, and the manager's preferences.