Through the experiences analysed in this book, both in member countries of the OECD (Organisation for Economic Cooperation & Development) and Latin America, and in spite of the broad heterogeneity of the contexts, a series of factors which have a positive effect on professional teaching development can be identified. Education policies in each country must identify objectives and directions appropriate to their particular circumstances. Good policies are essential to ensuring that professional teaching development provides the skills which teachers and professors will need throughout their extensive professional trajectory. Society needs good teachers and professors, whose professional practice corresponds to professional quality standards, and above all who fulfill the basic requirement of respecting students’ right to learn.