This chapter provides a comprehensive overview of motivation in organizations by examining internal, social, and organizational factors. It begins with classic theories focused on internal needs, such as Maslow’s hierarchy and McClelland’s theory of achievement, affiliation, and power, followed by Alderfer’s ERG model. Cognitive evaluation theory is introduced to explain how intrinsic motivation can diminish when external rewards are added. Social factors are discussed through expectancy theory, equity theory, and perceptions of organizational justice, all of which highlight how perceived fairness and expectations impact motivation. The chapter also introduces the concept of “flow” as an optimal motivational state. Organizational factors are explored through Herzberg’s two-factor theory and the job characteristics model, both of which link motivation to task design and work environment. Theories X and Y are presented to show how managerial beliefs shape motivational strategies. Contemporary applications, including human resource systems and talent management, illustrate how organizations implement these theories to sustain engagement.