Investigating the effect technology has on the secondary mathematics classroom instruction has been a growing topic in mathematics education since calculators and computers became readily available to students and teachers. Most of the focus has been on students use of technology to enhance their mathematical knowledge, while teacher use of technology during instruction has had limited research attention. The purpose of this study was to further understand the emergence of the roles of facilitator and mediator when secondary mathematics teachers used technology during instruction. The teacher role while using technology framework was a blend of Monaghans (2004) teacher roles and Zbiek, Heid, Blume, & Dick (2007) mathematical activities framework. Observations of three high school mathematics teachers, Bill, Joanne, and Mary, guided the discussions during individual interviews. Participants were selected because they were enrolled in or recently graduated from a technology rich mathematics education program. This selection was done to maximize the possibility that the participants knew how to use technology with the mathematics curriculum being taught. Individual pre- and post-interviews, video recordings of observations, and field notes were among the data sources. Participants were observed teaching four lessons, with varying schedules to accommodate each participant. Predetermined and emergent coding schemes contributed to comparative data analysis. The findings of this study show that not all participants took on the same role while teaching secondary mathematical activities. Conceptual and procedural mathematical activities affected the participants role while teaching with technology. An emergent theme of the source of mathematical activities, internal or external, helped illuminate the development of teacher roles while using technology. Procedural mathematical activities were found to only contain external sources of mathematical activities while conceptual mathematical activities contained both internal and external sources. A connection was established while comparing the source of mathematical activities with the teachers roles while using technology. The analysis indicated that the facilitator role was only observed when teachers had conceptual mathematical activities that involved internal sources. When an external source was observed, the teachers role was found to be that of a mediator.