The deployment of Self-Driving Vehicles (SDVs) is not merely a technological issue; its success also depends on the readiness of the surrounding environment. In urban spaces, SDVs are expected to reach a critical mass and spatial concentration, posing complex challenges that require extensive planning and preparation. Consequently, SDVs necessitate specific urban development interventions to ensure the safe operation of the technology. Such SDV-specific urban development is crucial for realizing the anticipated benefits of autonomous vehicles while mitigating potential drawbacks, which in turn requires an accurate understanding of urban SDV-readiness. While an increasing number of studies assess SDV-readiness at the national level, little is known at the city level. Our research develops an index to assess the readiness of cities for self-driving vehicles from a policymaker perspective. In 2025, we surveyed municipal policymakers from 50 Hungarian cities with public transport and populations exceeding 20,000. The Urban SDV Readiness Index integrates four dimensions: the current urban mobility context (baseline), the anticipated emergence of SDV-related challenges, the expected timeframe for required interventions, and the ease of overcoming implementation barriers. The overall readiness index of Hungarian cities ranges from 18% to 76% (mean: 45%), with larger cities generally reporting higher readiness levels. The ranking of cities based on the composite index highlights clear leaders and laggards, aligning closely with the cluster classification and providing an accessible benchmark for comparison. Results indicate that, from the perspective of policymakers, many SDV-related developments are expected to materialize only in the distant future. Overall, the index offers a policy-relevant diagnostic benchmark that can support municipalities in identifying readiness gaps and prioritising targeted interventions and capacity-building strategies.