Nature of science has for a long time been regarded as a key component in science teaching. Much research has focused on students’ and teachers’ views of NOS, while less attention has been paid to teachers’ perspectives on NOS teaching. This article focuses on in-service science teachers’ ways of talking about NOS and NOS teaching, e.g. what they talk about as possible and valuable to address in the science classroom, in Swedish compulsory school. These teachers are, according to the national (...) curriculum, expected to teach NOS, but have no specific NOS training. The analytical framework described in this article consists of five themes that include multiple perspectives on NOS. The results show that teachers have less to say when they talk about NOS teaching than when they talk about NOS in general. This difference is most obvious for issues related to different sociocultural aspects of science. Difficulties in—and advantages of—NOS teaching, as put forth by the teachers, are discussed in relation to traditional science teaching, and in relation to teachers’ perspectives on for which students science teaching will be perceived as meaningful and comprehensible. The results add to understanding teachers’ reasoning when confronted with the idea that NOS should be part of science teaching. This in turn provides useful information that can support the development of NOS courses for teachers. (shrink)