This paper uses firm-level data to assess whether telecom services are general-purpose technologies. We find that only Internet services are so: firm growth and productivity are substantially higher when Internet access is greater and when firms use the Internet more intensively; and it benefits firms of both high- and low-tech industries, firms of all sizes, and firms with and without exporting. Small firms benefit more from Internet than large firms do. In contrast, fixed-line and cellular services are not robustly related to firm performance.