This essay critically evaluates key motivational theories and their application in increasing employee engagement. It begins by defining employee engagement and its importance, then delves into several prominent theories. Maslow's Hierarchy of Needs is discussed, emphasizing how meeting employee needs at different levels can enhance engagement. Alderfer's ERG theory is examined, highlighting the concepts of existence, relatedness, and growth needs. Herzberg's Two-Factor Theory is analyzed, differentiating between hygiene and motivational factors and their impact on job satisfaction. Adams' Equity Theory is explored, emphasizing the importance of fairness and equal treatment. Finally, McGregor's Theory X and Y is considered. The essay uses examples to support arguments and considers the practical application of these theories in the workplace, offering insights for managers to improve employee engagement and, consequently, organizational performance.