For many years, teachers have been involved in developing the national curricula in Finland in various ways. Teachers' involvement in curriculum design and implementation has, during the last national curriculum implementation process, increased locally to strengthen their confidence in and knowledge of the national curriculum's multifaceted content. The purpose of this article is to broaden the knowledge of teacher involvement in the recent curriculum process in Finland; more specifically, to examine teachers' participation in local curriculum work. In this qualitative study, interviews were the primary method used to gather empirical data. Hansén's (1998) ideas of different levels of teacher professionalization are used as a framework for the analysis. The results show that ways of organizing involvement, management of involvement and use of time in the local curriculum process are crucial factors in teachers' participation and partly determine their degree of participation. The results also suggest that teachers' awareness of how the curriculum is linked to their collective collaborative and continuous work is relatively high, but it is not entirely clear how the four steps are integrated in the professional language.