As governments around the world struggle to govern a multitude of emerging technologies, they often seek to harmonize their regulatory approaches. But there are at least 10 different reasons why nations may seek to harmonize their oversight of a specific technology, and discerning which of these rationales will apply to a specific technology is critical for selecting the optimal harmonization approach. The traditional approach is the negotiation of formal international treaties, but, as exemplified by the challenges of cybersecurity, such treaty-based approaches are too resource-intensive and difficult to be effective for most technologies. Accordingly, a new generation of more informal international governance tools are being explored, often grouped under the term “soft law.” They include private standards, guidelines, codes of conduct, and forums for transnational dialogue. Read this free-access article from the subscription journal.