The research presented here is a group case study of students learning calculus in a Computer Algebra System (CAS) environment which examines the following research questions: What are students' perceptions of the role of technology in their learning? What is the students' relationship to CAS? What is the effect of learning in a CAS environment on students' conceptions of mathematics, as a subject? The primary data for the study consists of audio and video tapes of a group of students in a college course learning calculus using CAS software. This data was supplemented by interviews with the students as well as analysis of the students' homework and tests. Analysis of the data via the Didactic Triangle provides a lens through which to view the place of technology in the CAS classroom and through which to view the journey of each student during the course. The evidence of the study shows the importance of understanding the relationship students have to CAS in the mathematics classroom since it can act as an inhibitor of student work as well as an enhancement as it challenges them in profound ways with regard to their beliefs and attitudes about mathematics. (Contains 9 figures.)