 Today's postal services are so much more than letters. They deliver the 21st century digital economy for all, through a wide range of mail, parcels and financial services, providing innovative and inclusive solutions for citizens, business and territories worldwide. With the rise of digitalisation, postal services worldwide face significant challenges, but also tremendous opportunities. They need to develop and continuously transform their system to cater to the fast evolving needs of customers who increasingly depend on fully integrated physical and digital logistics. The Integrated Index for Postal Development, developed by the Universal Postal Union, constitutes the first global tool ever created to assess countries on four critical dimensions of postal development. Reliability, Reach, Relevance, Resilience. The top five performing countries in 2016 were Switzerland, France, Japan, the Netherlands and Germany. They achieved the highest scores on each of the four indicators. Their success drivers included quality, well connected, diversified and inclusive postal services. The top performing countries in each of the UPU's developing regions also show encouraging results. Poland, in the Eastern Europe and CIS, Singapore in Asia Pacific, Mauritius in Africa, Brazil in Latin America and the Caribbean, the United Arab Emirates in the Arab region. In some regions though, the postal sector is retreating, producing negative impacts to countries' social and economic infrastructure. Preventing postal infrastructure from delivering inclusive social and economic services reduces the country's likelihood of achieving the UN's sustainable development goals. Postal operators cannot ignite postal development alone. They need support from governments and the private sector. They also require a regulatory environment that is adapted to their expanding development role and activities. Many national posts still need to improve their operational efficiency, enhance their connectivity with global supply chains, diversify their portfolios beyond traditional segments and adapt their business models to match the transforming business environment. Supporting investments in public policies and enabling regulatory environment and diversified strategies by postal operators constitute the road to postal development. The Integrated Index for Postal Development relies on the Universal Postal Union's big data, statistics and key surveys. In this sense it is a unique tool promoting data-driven development. Ministries, regulatory agencies and operators will undoubtedly use it to achieve postal excellence in their countries.