Quantum computing presents a threat to the current cryptographic standards in place, supporting our digital scoiety. As our lives are increasingly dependent on electronic transactions, our society becomes increasingly vulnerable to distortions of digital trust. By taking a design science research approach, this thesis designs a risk assessment method to assess the societal risks posed by quantum computing to public key infrastructures. Through reviewing literature, user workshops, and expert consultation a Societal Risk Assessment (SRA) is made and preliminarily tested. By performing an instrumental case study of Logius as the Policy Authority of PKIoverheid, the potential impacts on society of the quantum threat become visible. This thesis was written as part of the research project HAPKIDO, investigating the transition to quantum safe public key infrastructure. The resulting SRA method is deemed useful, but remains somewhat complicated to apply.