Rare opportunity to lease a freestanding, single-tenant commercial building in the heart of Westbury's Eastern Nassau submarket. This 3,000 SF standalone property at 319 Union Avenue is fully built out for veterinary or medical use and is move-in ready for a qualified healthcare, animal care, or professional services tenant. The building features a steel frame construction with classic brick exterior and offers dedicated on-site parking — a premium amenity in this densely developed submarket. Its ground-floor, single-story layout provides full ADA accessibility and exceptional operational flexibility for a wide range of uses. Currently configured as a functioning animal hospital, the space includes clinical infrastructure ideal for a veterinary practice seeking immediate occupancy or a medical/healthcare provider looking to inherit a purpose-built environment without the cost and time of a ground-up build-out. The 0.23-acre (9,932 SF) lot offers ample room for signage, patient/client drop-off, and staff parking. Highlights: • 3,000 SF freestanding building — no shared walls, no shared lobbies • Dedicated parking on 9,932 SF lot • Veterinary/medical infrastructure in place • Flexible configuration for single-tenant occupancy • Steel frame / brick construction — built to last • Prominent Union Avenue frontage with strong visibility • Eastern Nassau submarket — convenient access to major thoroughfares Ideal for: veterinary clinics, animal hospitals, medical or dental offices, outpatient healthcare, physical therapy, specialty professional services.