This report examines the vital role of human resources in organizational success, specifically focusing on change management and organizational design. The report begins with an introduction highlighting the significance of HR in achieving organizational goals, using Marks and Spencer as a case study. It then explores changing business environments, including technological, market, and socio-cultural factors. The core of the report delves into change management theories, such as Lewin's and Kotter's models, and considers ethical and legal constraints. It also identifies barriers to change, such as ineffective communication and resistance, and offers strategies to overcome these challenges, including communication plans and employee involvement. Recommendations are provided for Marks and Spencer, emphasizing transparency and employee engagement. The report concludes by reiterating the central role of HR in implementing successful changes and achieving organizational success. References to relevant academic sources are also provided.