Psychology is termed as the science of behaviour. In its so popular meaning the study of the subject psychology equips the learners with such essential knowledge, understanding and skills that can prove a big helping hand to them in their adjustment with the environment. Perhaps this has necessitated to have a study of the subject psychology in the prescribed nursing curriculum both at the graduation as well as diploma levels. This book is specially meant for meeting the requirements of this course. To meet the needs of the students in a satisfactory way, the subject matter of the text has been divided into seventeen chapters dealing with the units, subunits, and topics of the prescribed syllabus. Attempts have been made in the text to integrate theory and applications of the principles of psychology by highlighting the implications of the related knowledge of the nurses as students and working professionals.