School development represents a field of educational research and practice in which the quality of schools, i.e. all their input and output factors, should be improved. Recent developments in the field concern ways of standard-based instruction and are mainly focusing on specific cognitive factors like subject matter knowledge, learning strategies, or problem solving skills. However, the purpose of this book is to focus on non-cognitive, i.e. emotional, and on general skills which also influence knowledge acquisition or school achievement and which have been widely ignored by school development programs so far.