This study constructs the Companion Animal Welfare Resilience Index (CWRI), a composite index measuring the structural capacity of national companion animal welfare systems to withstand and recover from external shocks, including economic downturns, natural disasters, disease outbreaks, and demographic shifts. Using 26 indicators organized across four sectors (Institutional Capacity, Service Infrastructure, Economic Capacity, and Vulnerability) for 28 countries, the index is constructed via Shannon entropy weighting applied to min-max normalized indicators. The resulting index places Australia first (CWRI = 100), followed by Denmark (82.8), France (78.7), and Sweden (77.5). Sensitivity analysis confirms that rankings are robust to alternative weighting schemes (Spearman ρ ≥ 0.849 across all specifications). To assess construct validity, regression analysis using the MARS State of Pet Homelessness Project (N = 16) confirms a statistically significant negative association between CWRI scores and companion animal homelessness rates. For comparative context, the widely cited WAP Animal Protection Index fails to reach statistical significance under the identical specification (p = 0.243), highlighting the added explanatory value of the CWRI's infrastructure and resilience framing. Exploratory sectorlevel analysis identifies Economic Capacity as the primary structural determinant of welfare outcomes, with the strongest specification explaining 72.1% of the cross-national variation in homelessness rates (𝑅2 = 0.721).
