Organization Behaviour Chapter 1 Definition, importance, historical background, Fundamental concepts of OB , challenges and opportunities for OB :It is a field of study that investigates the impact individuals, groups and structure have on behavior within an organization, and then apply that knowledge to make organizations work more effectively (Robbins 2003).An effective and efficient manager should focus on two key results. Management functions have been grouped in four categories- planning, organizing, leading and controlling. Characteristics of management are goal oriented. Economic resources, distinct processes, integrative forces, intangible forces, a science and an art together results through others It is a system of authority and multidisciplinary subject.OB focuses on how to improve productivity reduce absenteeism, and turnover, increase employee citizenship and job satisfaction. An organization consists of people and so it is also a social system.The field of OB draws primarily from the behavioral science disciplines of psychology, social psychology and cultural anthropology. Aras on which OB focuses are individuals, who will often be working with groups, which themselves work within organizations as well as all the interrelationships between them. Some of the specific themes held by OB are Personality Theory, Attitudes and Values, motives and learning, interpersonal behavior, group dynamics, leadership and teamwork, organization structure and design, decision-making power, conflict and its negotiation. OB is an interdisciplinary field. It has distinctly humanistic outlook. It is performance related. It consists of external environment as critical. It uses scientific method and it has application orientation.3 broad aspects of analysis are individual level, group level and organization level. Further to this , Wood (1997), provides a useful model for exploring behavioral events. He suggests that different levels of analysis can be applied when examining the significance of an organizational issue. He proposed 8 , namely individual, team, intergroup, organizational , inter-organizational , societal , international and global.A large number of people have contributed to the growth of OB as a discipline .Some of the most important works have been done by Adam Smith, Frederick Taylor, Henri Fayol, Max Weber, Mary Parker Follet, Abraham Maslow , B.F. Skinner to name a few. OB is an applied behavioral science that is built upon contributions from a number of behavioral disciplines. Main areas are psychology, sociology, social psychology, anthropology and political science also among many others.