Do chemistry teachers 'bring' into their instruction all the relevant variables or important predictors for concept development revealed by contemporary research? Do they organize and sequence their lessons in such a way as to help pupils learn? Is the scientific language utilized by chemistry teachers in the secondary schools appropriate to pupils' experience? In an attempt to answer these vital questions, 44 sample lessons of 20 chemistry teachers, randomly selected from 19 secondary schools in the state of Malacca, Malaysia were analysed using the 'Concept Instruction Category System' (CICS). The results suggested that this sample of teachers scarcely use most of the conventional determinants - especially instances and definitions of the concept - during the delivery of their instruction. Teaching appeared to be more relevant to concrete concept learning rather than to abstract concepts which are common in formal (chemistry) school learning. This sample of teachers relied on their instruction in demonstrating the use of concepts, describing/illustrating the concepts, and discussing the procedures of how to investigate the concepts in question. During these processes of teaching, teachers guided pupils to foster facilitition of concept understanding. The sample of teachers emphasized demonstrating (the use of concept), eliciting, and feedback strategies, as a primary teaching cycle, which was supported and reinforced by using corrective-feedback and guidance tactics. Unfortunately, teachers used scientific language that presented only situational meaning rather than abstract meaning. In general, this sample of teachers emphasized fact-giving with some experimental activities that were extremely didactic and teacher dominated. Despite the 'transmission nature' of instruction employed by this sample of teachers, generally they did sequence instructional events according to models for the internal process of learning. The sequential order of instructional events suggested in the model are more relevant for teaching a small unit or part of a lesson plan. The application of a cluster analysis technique revealed three predominant styles of teaching in this sample of teachers - i. e., styles 1,11 , and in, each having distinctive characteristics, although there were overlapping and shared qualities between the groups. In a comparative study, a number of dominant features of the three styles, especially experimental activities, fact-giving and teacher domination, were similar to some samples from Britain, Canada, Kenya and Nigeria. Some implications of the findings for chemistry (or science) teacher education and school teaching in Malaysia are suggested, limitations are cited and some suggestions for further research are put forward.