In the presented studies one of our aims has been to deepen our understanding of features of a school leadership that promote school development. Conceptions of teachers and school leaders about factors influencing the process of school development have little in common with the conceptions expressed by central authorities. School development from an actor perspective is about finding solutions on problems encountered in the everyday teaching situation. The evidence suggests that the teachers perceive that they are more successful in helping the pupils to learn and develop when leadership and school development process is problem based and they state that their confidence in the school leaders has increased. They also perceive better possibilities to influence important matters in the daily work. Shared aims concerning central pedagogical ideas in combination with enhanced variation in ways of teaching has increased and a good climate for dialogues and learning in the staff is also reported as well as a deeper understanding of the mission and of the instructional pattern among the teachers. The empirical basis for the conclusions is three studies in which surveys, interviews and observations have been used