The Smart Cities Council, a global advocate for smart city adoption, states that the term “smart cities” still lacks a universally agreed upon definition. However, the term generally refers to the integration of information technology (IT) with the management and operation of civic functions. As these civic functions can include operational technology (OT) elements that monitor and operate physical systems, a smart city system can be seen as representing the intersection of the IT, OT, and public service domains of practice. All three domains are represented by mature fields of practice, but their combination in cross-domain projects can expose gaps within each domain, where key characteristics important to one domain might not be considered by the others. If not addressed, these gaps can introduce security, safety, and privacy risks, including risks to critical infrastructure and its underpinning technology.