First appearances can be deceiving—51-room Santo Mauro is housed in a former Belle Époque palacete that suggests a conservative interior. But a renovation in 2000 introduced minimal furnishings; a color palette of black, white, and chocolate; and chill-out music in the common areas. Of special note are rooms 40, 41, and 42, which are situated on the ground floor and open onto a lush garden with full-grown palm trees and bubbling fountains. The garden serves as a bar by day, and at night in the summer months, guests can enjoy a candlelit dinner there. Meals are also served in the original library, which, fiber-optic chandeliers aside, retains much of its old-world charm. While the hotel is tucked away on a side street in Chamberi, one of the city's most elegant neighborhoods, it's within walking distance of Paseo de la Castellana and the Serrano shopping district.

Closed August.

Set in a redone 19th-century building near the Plaza de Colón, in the trendy Salamanca district. The hotel's lobby, bar, and other public spaces have black and white checkered floors and light furniture and exude the airy charm of an old seaside resort updated for the 21st century. Rooms, designed by P. Ortega in calming beiges, browns, and warm oranges, have mood-stabilizing effects that rival lithium. Unfortunately, the pompous, overdressed restaurant falls short of the design standards of the rest of the Adler. But you're in Madrid—why would you dine in your hotel, anyway?

The Bauzá is one of Virginia Figueras's two masterworks in Madrid; the other is the Hotel de las Letras. Located in hip Salamanca near the museums, the Bauzá innovates with airy citrus color schemes in its 170 rooms and suites, as well as in seven small, tasteful apartments decorated in light woods. The latter might be the best way to go, especially for families. The so-called "apart-hotel" concept is appearing in myriad places around the world, and for good reason. It's a great boon to be able to cook breakfast or entertain guests in your room, a privilege once reserved for visiting dignitaries or presidential-suitesters. Still, this concept is not about savings; it's about a different way to experience the city: Shop for jamón ibérico and torta del casar cheese in the market, and then throw a cocktail party for the Madrileños at "your place."

Once the 18th-century summer residence of the Cardenal Lorenzana, Archbishop of Toledo, this converted hostel is built on top of the old city and set within shady gardens. Guests can ride an escalator into town. There are just 27 delightful, though modest, rooms with vaguely Moorish wood furnishings, and they fill up quickly, so book well ahead. The Cardenal also features a celebrated restaurant.

The Hesperia's lobby is beautiful, done up in shades of warm orange with clean lattice work, lots of greenery, and wide-open spaces. You could sit for hours in the lobby lounge, just reading a book and soaking up the sunlight. Opt for a junior suite or a deluxe double rather than the entry-level rooms, which, though well-appointed and tastefully furnished, are surprisingly cramped. The Hesperia understands that extensive Scotch whiskey lists aren't just for grandfathers anymore, and its friendly, nonpompous bar offers the best selection in the city. Equally impressive is the basement restaurant, the famed Santceloni. This hotel is located in the quiet Salamanca neighborhood and you'll need to take a taxi or metro most places, but the metro stop is right across the street.

Out of all the city's new design hotels, this is the one that most carefully blends old and new, keeping an eye on its architectural past while still creating an utterly modern guest experience. All 37 rooms are in chic shades of black and have DVD players and minimalist bathrooms in gray marble. Windows have been kept big, their shape unaltered from the original 1870 design. The Meninas' original hardwood staircases and landings are another beautiful reminder of what the building once was, and of how respectfully the building has been renovated. The location, near the Opera, is excellent. One downside: Wi-Fi only works in the lobby; rooms have cable Internet connections.

This classically styled Relais & Châteaux boutique hotel in an 1880s mansion, located in a quiet residential area near Colon Square, has a relentless dedication to serving the needs of those who wish the modern-design revolution had never taken place, that all the minimalist Deco lamps, rock sculptures, and recessed lighting fixtures would be ritually burned in a big bonfire, and that hotels would return to an age of ornate ballrooms full of crystal and flowers. The Orfila opened in the late 1990s, but even its gaudy gilded-wreath logo hearkens back to an earlier age. No expense has been spared on materials, maintenance, or service. The 32 plush rooms (12 of which are suites) come in tasteful stripes, low-key florals and with époque furniture. The restaurant, El Jardín de Orfila, caters to an older crowd and keeps with the classic theme: They wouldn't even think of placing your bottle of wine on the table, or of allowing you to manage your own napkin.

Opened in June 2005, this 6-story 19th-century town house is one of the newest of a young chain that's rapidly engulfing Madrid (plus several other Spanish cities). Centrally placed in a businessy area near the National Library, its 75 rooms are proudly wired (after all, the group's acronym HT stands for High Tech): In-room computers have free fast Internet, and there are flat-screen satellite TVs and the group's signature whizbang shower units with hydro-massage and sauna built in. Most of them also have in-room stationary bikes for simultaneous surfing and exercise; the ten that don't are family-size to sleep up to four. The public spaces are similarly space-age, with a central lit-from-within command module of a reception desk in the lobby, glass-walled bathrooms, and molded plastic chairs. The facade, on the other hand, is reassuringly staid.