This study is an attempt to understand better the complex nature of tertiary teaching by identifying and investigating the attributes of a group of excellent teachers in science departments of the University. In working with this group of teachers we examined what they say about their teaching and what they do in their teaching practice. Our findings, as well as confirming much of the existing literature at primary, secondary and tertiary levels, emphasise the strong link between the teaching practice and research commitment of our excellent science teachers; as well as the key roles played by interpersonal relationships and the "person" of the teacher. We propose that purposeful reflective practice integrates the many dimensions of teaching for this group of excellent science teachers. We present a theoretical model that can be used to assist novice or less experienced university academics in their development and understanding of teaching excellence at the tertiary level.