This luxurious, 110-room boutique one block from Union Square is an enclave of posh rooms and pampering service in a dense city. There aren't many features here -- just a gym and a small business center -- but its top-notch service and luxe room amenities make it one of the city's most special hotels.

Known for its Redwood Room bar, the Clift's hip scene is typical of the Morgans Hotel Group, which bought the historic hotel from Four Seasons and reopened it in 2001 after a makeover by Philippe Starck and Ian Schrager (the latter of Studio 54 fame). The lobby and the 350 small but comfortable rooms are short on amenities but high on scene and style.

Not as conventionally luxurious as some Union Square-area competitors, but so filled with interesting touches and thoughtful extras that you won't notice. The rooms are smallish but have wonderful beds, quirky-yet-elegant style, and state-of-the-art technology. The service is rock solid. And the lobby is a great place to hang out, especially for the free wine receptions and morning coffee.

Taken over in late 2011 by Singapore-based Grace International, this 136-room historic hotel in swanky Nob Hill has an attentive staff, a quiet, intimate atmosphere, and old-world grandeur to spare. Homey rooms, though not quite luxurious, are large for the price. Plus, guests can use the indoor pool and other facilities at the excellent spa for free. All in all, one of the city's best boutiques.

The stylish, 200-room Hotel Vitale has an ideal location on the Financial District's revitalized waterfront, surrounded by fine dining. Its beautiful guest rooms, top-tier services, reputable spa, and numerous freebies -- Wi-Fi, daily yoga, passes to use the nearby YMCA's lap pool -- make it a great luxury choice.

An outpost of the generally solid "lifestyle"-focused chain, the W San Francisco in the SoMa art district offers clean, airy rooms, and above-average amenities in a whimsical, stylish setting. But despite efforts to seem boutique-y, the W is still a big, national chain at the end of the day, and the approach is less about personal touches than overall atmosphere.

The 182-room Villa Florence in Union Square admirably rises to the challenge of bringing Italy's culture and countryside to one of San Francisco's loudest, busiest, and most commercial districts. Rooms combine up-to-date technology with old-world style, but the hotel goes overboard on the Italian theme, and its amenities and services are uneven.

A classy upper-middle-range boutique right near Union Square's high-end shopping, the Prescott offers a Wolfgang Puck restaurant and charming little touches like nightly wine hours, free cookies, and free morning coffee and tea. But the rooms need some updating, so if the price hits $250 to $300, look elsewhere.

The stylish Harbor Court, a Kimpton hotel, occupies a historic, YMCA building; as a result, its 131 guest rooms are about half the size of most standard rooms. However, freebies like morning coffee, Wi-Fi, and an evening wine reception, and a great location on the Financial District's revitalized waterfront make it a reasonable choice for couples and solo travelers.

This 94-room Union Square boutique, themed after 1920s and '30s literary salons, is a bit quirky, with fairly hands-off service and few amenities. But the tiny quarters are nicely furnished with up-to-date amenities, there's a daily wine hour in the reading-room-style lobby bar, and an on-site bistro offers up well-priced Californian fare.