The Hajj is an annual religious mass gathering that takes place in Makkah, Saudi Arabia. The complexity

of its system is multidimensional, with religious, political, cultural, security, economic, communication, operational, and logistic unique challenges. This year, yet another stampede tragedy that caused around a 1,000 deaths and severe injuries, capturing worldwide media attention and exacerbating existing political tensions across the Gulf coasts was faced. Planning is important but the planning process is more important, requiring systematic analysis based on accurate collected and targeting root cause factors. Every year, the Hajj provides us with important knowledge and experience that will help preventing such events. This will only be possible if the initiative to extract all possible lessons learned are taken. The medical and public health communityin Saudi Arabia must learn from other scientific fields where much more quantitative data-driven approach to identify problems and recommending solutions