This study examines the history teacher's role in construing and enacting an innovative way of teaching the subject to first year secondary (or Secondary One) students in schools in Singapore. The teacher's response to curricular change is examined from the perspective of the individual teacher. The five teachers who participated in the main study formed the data source. A variety of methods was used. The emphasis was on the exploration and elaboration of the individual teacher's construction and enactment of his or her role in curricular change and how that role changed over time. The repertory grid employed in the main study was designed so that teachers construed the experiences associated with their roles as History teachers. The grid was elicited from the teachers at the beginning and at the end of the main study. As the grid was elicited on two occasions, it served as a repeated measure on which to structure the sequence of report and reflection that all five teachers engaged in with the researcher over a period of two terms (ie. from January-May, 1988). In addition, other data collection methods were chosen that complemented this emphasis on the individual and the extent of change. Each teacher was asked at the beginning of the main study to write about his or her work and explain how s/he planned lessons for Secondary One History students. After trialling the innovative materials for a period of one term, each teacher was asked to complete an open-ended questionnaire on teacher beliefs, planning and actions. The teacher was also given an opportunity to evaluate the innovative mode of practice. The teacher was also given an opportunity to evaluate the innovative mode of practice. Additional data in the form of transcripts of interviews and classroom teaching were available to the researcher. The data provided by the study support the belief that teachers can make or break an innovation since they control implementation.