The World Customs Organization (WCO) represents 185 Customs administrations that collectively process approximately 98% of world trade. In the era of digitalization, these border authorities find themselves in the epicentre of global e-commerce, influencing the country’s economic competitiveness, defining the ability of its small businesses to reach global markets, and protecting its citizens from illicit trade. With the level of national Customs development becoming the touchstone of overall socioeconomic performance, it is imperative to ensure that this development is speedy, harmonized and coordinated. This is where the WCO, with its mandate to build capacities and promote cooperation, comes in to fill in the gaps. A few days ahead of the WCO-UPU Global Conference 2023, dedicated to cross-border e-commerce, Ian Kerr spoke to Dr Kunio Mikuriya, WCO Secretary-General, about the evolving role of Customs, the challenges and opportunities they have in common with the postal sector, the importance of trust for the smooth movement of goods across borders, and why cooperation, specifically with the Post, is in Customs’ DNA.