Feline coronavirus (FCoV) is a widespread viral pathogen in domestic cats. Highly pathogenic FCoVs can cause feline infectious peritonitis (FIP), a systemic disease. The recent emergence of recombinant and highly pathogenic variants, including FCoV-23, highlights FCoV's capacity to rapidly evolve through recombination, mutation, and large deletions in the spike (S) gene. These genetic changes, particularly within domain 0 of FCoV-2 and in the furin cleavage site (FCS) of FCoV-1, are increasingly recognized as important determinants of FCoV pathogenicity. However, the evolutionary and epidemiological mechanisms driving the emergence and spread of pathogenic FCoV variants remain poorly understood, largely due to limited genomic surveillance and insufficient whole-genome sequence data. This project aims to expand global genomic surveillance of FCoV-1, FCoV-2, and FCoV-23 through streamlined clinical sample processing, whole-genome sequencing, and real-time phylogenetic tracking using a publicly accessible NextStrain (CatStrain) platform. The short-term goal is to improve the detection of co-infections, recombination events, and emerging pathogenic variants in domestic cat populations worldwide. The long-term goal is to develop molecular diagnostic tools capable of rapidly identifying highly pathogenic FCoV variants to guide timely antiviral treatment and outbreak mitigation strategies in high-density cat populations, including shelters and free-ranging cat colonies. By increasing the availability of global FCoV genomic data, this project will provide key insights into the evolution, geographic distribution, and transmission dynamics of FCoV, ultimately strengthening preparedness for future epizootics caused by emerging FCoV variants.