11 Best Spas in Paris, From Dior to La Mer | Condé Nast Traveler

"Discreetly tucked inside a historic townhouse off the Champs‑Élysées, this opulent, lab‑like space has drawn locals and visitors since the 1970s, when biologist Yvan Allouche and physiotherapist Josette Allouche founded it. A clinical, highly personalized approach starts with a diagnostic using both instrumentation and expert eyes to assess hydration, trans‑epidermal water loss, elasticity, pigmentation, and sebum. From there, a custom facial delivers a glow that lasts—provided you follow the beautician’s regimen for lifelong maintenance." - Kasia Dietz