The 19th-century Art Nouveau building that houses the H15 Boutique Hotel has had numerous incarnations over the years and many owners have changed details of its facade and interiors. When the Soviet Union turned the property into its embassy in 1924, the government added hammer-and-sickle symbols and sculptures that remain to this day. During World War II, Poland was under German rule and the building became Wehrmacht quarters, and from 2007 to 2012 the property underwent a multi-million dollar restoration that left many of the soviet-era relics intact. 

The lobby, once the building's courtyard, now has a glass atrium ceiling, a chic black-and-white checkered floor, and chairs that recall the mid-century swan and egg designs with playful shapes and colors. The restaurant has neoclassical molding and columns, mod black-and-yellow Oswald chairs, and Milton Greene's photos of Marilyn Monroe adorning the walls. A couple of the meeting areas are large repurposed guest rooms, but the "Historical Room" is an impressive, ornate space preserved from the days when the building was home to the Soviet embassy. The hotel attracts both leisure tourists and business travelers.

The H15 Boutique's location in central Warsaw is slightly better for business travelers than tourists, but it has advantages for both. Executives visiting Warsaw for meetings will be able to walk to several major offices. The Warsaw Stock Exchange is 14 minutes away on foot. Several tourist attractions are a short drive or public transit ride away, including the Warsaw National Museum (four-minute drive or 15 minutes by public transit), Lazienki Park, the largest park in Warsaw (five-minute drive or 15 minutes by public transportation), and the Old Town with its Royal Castle (10-minute drive or 20 minutes by public transportation). Warsaw Chopin Airport is about a 20-minute drive or 40 minutes by public transportation.

Architect Mariola Tomczak was inspired by '50s space age graphics, mid-century modern furniture, and pop-art visuals in creating these individually designed guest rooms. Funky touches like striped hallway runners, hot-pink slipper chairs, and lime-green throw pillows add a lot of decorative punch to white walls and simple wood floors. Categories range from Standard Rooms (280 square feet) to Two Bedroom Suites (about 970 square feet). All rooms have a queen-size bed, wood floors, desks, and custom artwork. As the rooms get bigger, the living room and dining room areas grow. In addition to chairs, some suites have couches, coffee tables, and dining room tables for in-room meals. Guest amenities include LCD TVs, safes, bathrobes, free Wi-Fi, and kitchenettes with a mini-fridge and an espresso-maker. While many of the bedrooms integrate playful Day-Glo colors, the bathrooms tend to be sleek and black-and-white with marble walls and modern fittings, though many only have showers. Cribs and infant beds are free. 

The H15 Boutique's amenities are, like the hotel, distinctive and enticing. In addition to the mod seating, the lobby also has a grand piano and foosball table. The Signature Restaurant serves innovative continental dishes such as sea bass with grapefruit-tamarind dressing and keta caviar and baked pumpkin salad. Breakfast is also served for a surcharge. A fitness room has a handful of machines, enough to keep a moderate exercise enthusiast happy, and massages are also offered on-site. Bikes can be rented from the property to use around town. The meeting spaces range from the casual Prestige Suite to the boardroom-style Penthouse and the palatial Historical Room, which maintains much of the Soviet-era embassy style. A hotel shuttle to and from the airport is offered for a fee. Hotel cars can also be used for getting around Warsaw. On-site parking is available for an extra fee.