This report provides a summary of the Inaugural Event of the OECD Global Forum on Digital Security for Prosperity ("Global Forum") held on 13-14 December 2018 in Paris, France. The event gathered 240 experts and 50 speakers from governments, businesses, civil society, the technical community and academia of 40 countries. They examined the roles and responsibilities of actors for cybersecurity, with a focus on good practice for the governance of digital security risk in organisations, and how to improve digital security of technologies throughout their lifecycle. They discussed issues such as whether organisations can "hack back" in response to an attack, how to encourage "digital security by design" in products' development, the role of certification, as well as how to foster the responsible disclosure of vulnerabilities by security researchers.