Approximately four out of five employees globally are either disengaged or actively disengaged at work. Recent data shows a rapid drop in engagement in the leadership and management sector of organizations. This literature review explores the efficacy of Positive Psychology Interventions (PPIs) designed to increase the state-like constructs of Positive Emotions and Psychological Capital (PsyCap), a construct combining Hope, Efficacy, Resilience, and Optimism). Results from multiple studies show small to medium effect sizes for Positive Emotion and PsyCap Interventions for increasing employee engagement, productivity, job satisfaction, commitment to the organization, organizational citizenship behavior and reductions in stress, absenteeism, and intention to leave the organization. Individuals low in targeted state-like traits pre-intervention experience greater growth than individuals high in the state-like traits. Brief, online, self-directed interventions were effective and longer, in-person, group interventions showed greater benefit. No negative side effects were discovered. Limitations are discussed and an appendix of evidence-based interventions is provided. PPIs targeting Positive Emotions and PsyCap are a scalable, cost-effective strategy to increase employee engagement and satisfaction at the workplace.