In a recurring dream, I walk down a hallway in my apartment and discover a whole wing I never knew existed.

Fantastic! I now have a spacious dining room, library and guest suite.

I suspect many people living in cities where space is the ultimate luxury share this dream. And while many make do with limited space, living in just one room is particularly challenging. It's not just city dwellers coping with that challenge, but also students, seniors and those decorating a pied a terre.

Designers have some guidelines for making the most of living in one room. The first step, they agree, is assessing how you live.

Do you work at home? Do you like to entertain? After a thorough editing, how much stuff do you have left to store — clothing, books, shoes, DVDs, etc.?

On page 1 of her book "Design Rules" (Gotham, 2009), decorating diva Elaine Griffin writes, "Whether you are a studio apartment dweller or are gifted with a sprawling suburban domain, the design rules for the public spaces are the same."

Except the rules are even more important when you must make the most of one room.

The biggest issue in designing for one-room living is separating public and private space, said Kenneth Brown, a Los Angeles interior designer who appears on "reDesign," on the Fine Living Network and HGTV.

"Nobody at a dinner party wants to be staring at a bed," Brown said. For a one-room project featured on his show, Brown used a bookcase as a room divider to separate the public and private areas of the room, as well as to store books and provide a stand for a swivel TV.

He is a fan of the new-style Murphy beds, which he said are both sleek and comfortable. He masks the Murphy beds with custom finishes such as paneling, antique mirrors and art work to blend with the architecture of the room. One he especially recommends, from Zoom-Room, rolls down from behind a panel where you can hang a flat-screen TV.

While each room differs according to how his clients want to live (how much space they want devoted to entertaining, to a home office, etc.), Brown said there are rules that always apply:

• Don't be afraid of big pieces. Lots of small ones will clutter a space.

• Select furniture on legs so you can see under the piece.

• Don't float the furniture in the center of the room.

• Try lining the walls with two large sofas.

• Select a coffee table that might double for dining.

• Commit to one color and bring in different textures. That way the walls recede and the eye is not stopped by an accent wall.

• Create zones in your room with lighting. For example, hang a chandelier over the entertaining area.

Brown believes concealing stuff in pretty boxes is key to living artfully in one room. He is a fan of the Container Store for finding creative storage solutions.

Ron Marvin, an interior designer who appears on the HGTV show "Small Spaces, Big Style," has designed two one-room apartments for himself, in San Francisco and New York City.

"First, think about what you need the space to do," he said. "Think of your room as a beautifully appointed hotel room."

Marvin believes in allowing for the luxury of a queen-size bed and loves lamps, which he said have a cozier effect than overhead lighting.

As for wall color, he advises, "don't be afraid of the dark. Dark colors make the walls recede. It is only one room — experiment with wall color.