The minimalist main bath in designer Lori Kanter Tritsch’s Beverly Hills home features a shower with Fantini fixtures and a soaking tub, both in white terrazzo.

Lined with richly veined Arabescato Corchia marble, the primary bath of Sidney Torres IV’s New Orleans residence features a vintage Bagues chandelier and vanities designed by architect Lee Ledbetter, who renovated the 1865 Italianate mansion. The tub fittings are by Waterworks.

This midcentury marvel in Southern California was revamped by architect William T. Georgis, who lined the walls of the primary bath in cedar. The tub is by Waterworks with Dornbracht fittings and a painting by Amy Sillman animates the dressing room beyond.

The calming main bath of interior designer Bryan Graybill’s Hamptons estate features a vintage Europhane ceiling light, Woka Lamps Vienna sconces, and a Catchpole & Rye tub outfitted with Waterworks fixtures; the floor is by ABC Stone.

There’s a striking interplay of light and shadow in the primary bath of this Palm Springs retreat by architecture firm Marmol Radziner, which imported silver travertine from Tuscany for the the walls. The tub is a Claudio Silvestrin design by Boffi, and the tub filler and shower fittings are by Dornbracht.

Edgy art meets distinctive design at this Connecticut home crafted by designer Ellen Hamilton. In the light-filled main bath, antique oak wall paneling and millwork are bathed in shades of washed pale-blue milk paint. The chaise is by Vladimir Kagan, the sheepskin area rug is from Beauvais Carpets, and the hanging light fixtures, designed by Hamilton, are from Remains Lighting. American sculptor and photographer Petah Coyne’s 2007 Tetiaroa—made of silk flowers, chicken-wire fencing, and peacock feathers, gives the space a magical air.

French interior designer Nathan Litera’s transformation of a 300-year-old Belgian château included this debonair powder room, which features vintage Belgian sconces flanking a vintage French mirror and an antique marble sink with Volevatch fittings.

For Philippe Austruy and Valérie Bach’s Brussels townhouse, Pierre Yovanovitch installed a spiky Ilkka Suppanen pendant light and a Marlène Mocquet painting in the main bath. The oak bench is a Yovanovitch creation, and the floor features a striking pattern of white and gray marble.

In the Bulgari family’s opulent Marrakech riad, Spanish designer Pablo Paniagua clad the walls and counters of a guest bath in traditional ceramic mosaic tiles.

In model Adriana Abascal’s Paris apartment, designed by Luis Laplace, a work by Gregor Hildebrandt overlooks the primary bath’s Volevatch tub and filler, which are accompanied by a vintage nickel table, a Jean-Claude Delépine for THG towel warmer, and enviable city views that stretch to the Eiffel Tower.

Art dealer Stacey Winston Levitan’s stunning mountain retreat, conceived by Scape Design Studio and Susan Marinello Interiors, features a glamorous main bath sheathed in Athens Grey marble. Fittings for the shower, sink, and tub are by Kallista, while the countertops are Arabescato marble.

The beautiful, light-filled main bath in designer Lillian Fernandez’s dream house in Palm Beach is a study in soothing blues.

With interiors by designer Dara Stern, this East Hampton home by Robert A.M. Stern exudes classic elegance and cozy luxury. In the primary bath, the fixtures and fittings are by Waterworks, the sconces are by RH, and the stool is by Made Goods; the floor is Thassos tile inlaid with strips of Kromoglass.