Could a QR code open up the world? That is the question in Estonia as it takes a lead in global efforts to develop digital vaccine passports. The small, tech-savvy Baltic EU member state is working on a pilot project with the World Health Organization on how globally recognised electronic vaccine certificates might work. Marten Kaevats, an adviser to the Estonian government on technology, said the primary issue for the project so far is to ensure that anyone checking the certificate can “trust the source”. “Both the architecture and the solution should work both in Eritrea and Singapore,” Kaevats said. While Estonia already has its own system of electronic health records with vaccine information, most countries in the world do not and there is no mutual recognition across borders. There are now many digital vaccine passport initiatives cropping up globally that are raising urgent questions about privacy and human rights.