The language of the "new professionalism" in teaching in the literature over the past decade is a moral language stressing the moral nature of teaching which requires teachers to abide by ethical standards in their classroom teaching. Professional codes fit into this context since they are prescriptive, framed in the moral language of right and wrong, describing conduct which members of the profession should or should not engage in. This paper presents the results of two surveys, one in 1990 and the second, a replication, in 2000, which explored teachers' perceptions of the importance of a code of conduct for the profession. The design of the research which includes quantitative and qualitative methodologies is described. The main research instruments are questionnaires to which a response rate of over 90% was achieved in both years. The sample consisted of the post-primary teachers in schools within the Kildare Branch of Association of Secondary Teachers in Ireland (ASTI). All secondary or grammar schools in the Kildare were represented in the ASTI The analyses of the responses in both surveys are presented. The findings suggest suggests that (i) there is an increasingly widespread perception among teachers of the need for a professional code; (ii) teachers appear to have a much stronger preference for an advisory code than for one with sanctions; (iii) teachers, especially females, would be more likely to report than not to report misconduct. (iv) teachers' perceive a need for pre-service education in professional ethics; (v) there are relatively high levels of uncertainty, especially among female teachers, about some of the issues raised in the study. The recommendations which emerge from the study suggest that (i) a code of conduct for teachers is called for; (ii) pre-service teacher education in professional ethics is warranted; (iii) widespread dissemination and discussion of a code of conduct among teachers and on-going professional development in the area of the ethical dimension of classroom teaching might reduce the uncertainty among teachers found in the study. With the recent development of the Teaching Council with its remit in relation to the areas considered in the paper, these findings are particularly timely in Irish education