The paper examines communication and cooperation between principals and the school owners, the municipalities. The findings show large variations concerning the topics, structures and nature of the discussions between the schools and the municipalities. The variations are attempted understood in relation to differences in tradition, history and organization of the municipalities. The cooperation is discussed in relation to sustainable school development in the municipality. The data analyzed are mainly collected by means of close observation of three principals' work during four weeks, including meetings the principals participated in during this period. In addition, I have had conversations and more structured interviews with the principals. I have also done interviews of pupils, leader teams, teachers, others in the staff and parents. One of the principals work in a smaller lower secondary school, one in a smaller and one in a larger combined primary and lower secondary school. The schools are situated in different regions in Norway with large variation in relation to size, population density and economic base. Some of the background for this analysis is the changes in the management of the compulsory education in Norway. Traditionally the government have governed our primary and secondary schools. This is still the case, but the way this happens is changing. In the 90s, the national administration of education in policy was reorganized in Norway. A White Paper, St.meld. nr. 37 (1990 - 91) and a Bill, St.prp. nr. 75 (1991-92) aimed at introducing a more political basis for management by objectives. Among others in 1997 we got a new detailed national curriculum. In 2000 the National Board of Education was set up to: management of all national examinations, development of assessment procedures and surveys, collection and publication of statistics and secretariat assistance in connection with work on syllabuses etc. Another kind of change came in 2004. Up to then the central authority had played the employers' role in negotiations on teachers' salary and conditions. Now the teachers have to negotiate directly with the principal, the management in the school and the municipality in these matters. The development is that in administrative questions and tasks, more responsibility is given from the government to the municipalities, and then again many municipalities delegates more responsibility to the principal and to each school. But at the same time as the government gives more responsibility to the local communities, they also bring in a new system of control by national tests. The work is a part of a larger study about the relation between three principals' use of their educational competence in relation to the students' work and activity of learning in primary and lower secondary school. The larger study is a part of a Norwegian research project, Successful School Leadership (SOL).