Positive teacher attitudes are considered an important prerequisite for the successful inclusion of students with special educational needs in the mainstream classrooms. This study surveyed teacher opinions about inclusion in Finland (N = 298) and Brandenburg, Germany (N = 163), two educational systems in which the number of students transferred to segregated special education is exceptionally high in international comparison. For the measurement of attitudes a ten-item scale, Teachers' Attitudes towards Inclusive Education (TAIS) was used. The results showed that Finnish teachers were more positive towards inclusion than Brandenburg teachers (d = 0.46). The Brandenburg teachers were especially worried about the extra work caused by inclusion. This concern was possibly related to the different structures of educational organisation. Additional support services were more easily available for the Finnish teachers than for their Brandenburg colleagues. It is argued that teachers' concerns should be addressed to promote inclusion in schools.