School Psychology is a field that applies principles of clinical psychology and educational psychology to the diagnosis and treatment of children's and adolescents' behavioural and learning problems. School psychologists are educated in psychology, education, child and adolescent development, child and adolescent psychopathology, learning theories, family and parenting practices, and personality theories. They are knowledgeable about effective instruction and effective schools. They are trained to carry out psychological and psychoeducational assessment, psychotherapy, and consultation, and in the ethical, legal and administrative codes of the profession.