At the heart of the success of any school improvement process is teachers willingness and ability to change and improve their knowledge, attitudes and practices. This is depended on the support given to teachers to gain such knowledge and skills. This book, therefore, challenges the school leader to use creative and proactive strategies to implement professional development and accountability policies in such a way as to enhance the professional collaboration of teachers to improve the educative process. The author further argues that the principal s support of professional development activities is crucial to the success of the professional growth of teachers.