This doctoral thesis addresses the growing pressure on warehouses to process customer orders efficiently amid rising demand and increasing operational challenges such as globalization, higher customer expectations, and labor shortages. Despite technological advancements, many warehouses still rely heavily on human order pickers, whose roles are both critical and increasingly difficult to fill and retain. While previous research has focused on optimizing warehouse processes, it has largely overlooked the impact on the workers themselves.nnThis thesis shifts the focus by placing human order pickers at the center of warehouse planning and execution. It aims to develop system interventions that enhance both operational efficiency and worker well-being, promoting economic and social sustainability. The first contribution is a comprehensive review of how human factors are currently integrated into academic literature, compared with insights from interviews with pickers and supervisors. This reveals a significant gap, especially in addressing psychosocial aspects.nnThe second contribution introduces a participatory system that involves employees in operational decisions, improving job satisfaction and reducing fatigue without sacrificing productivity. This system was tested in both lab and real-world settings. The third contribution examines the long-term effects of this system, showing sustained benefits over six months. Finally, analytical models demonstrate how managers can optimize the system’s impact. The thesis concludes with recommendations for future research to holistically improve order picking systems.