Bookshelves tend to live quietly in the backgrounds of interiors, really coming alive with their contents. There are, of course, the beautiful built-ins that shine in upscale design magazines -- notable with their exquisite crowns or fluting, elegant trims, exotic wood or paint finishes.

But in recent years, freestanding bookshelves are turning heads. They've been elevated from mundane brown boxes to centerpieces with dynamic design elements in a range of styles, finishes and occasionally bold colors -- all of which spell modern, even with traditional roots. While edgy contemporary pieces have been available in Europe for decades, they now are making much more of a splash at retail here.

Modular, architectural or sculptural, these bookcases are no wallflowers. They lean, they anchor, they float, they divide space. And some do it in most unconventional ways -- in circular frames, organic shapes, cubes that create engaging compositions on the wall, shelves that are asymmetrical or slant sideways. Even wall systems designed to house flat-screen TVs offer relief from the convention of the grid.

One catalyst for rethinking the look of bookshelves is the shrinking of space. Downsizing -- which may include shedding huge collections of books, as well as the advent of the Nook and other e-readers that are slowing the acquiring of hard copies -- means that less dedicated storage may be necessary.

So especially appropriate to apartments, condos and homes with smaller interiors is the etagere. Once considered a dust catcher for tchotchkes, the etagere has emerged as the new, improved "bookcase light."

"There's not a place you can't put one," says Bob Williams, creative director for Mitchell Gold and Bob Williams Home. "It can go into hallways and more public rooms. I've got one in my bath for towels. They're quite versatile.

"What I like about etageres," says Williams, "is that they have a smaller footprint. They give a room some height. They're not dominant like armoires that were so popular 10 to 15 years ago. They can fit in narrow spaces. They can be used as room dividers. They're almost sculptural but functional, depending on how you decorate them, with books in various color and shapes or small objects."

The slim shape also is a natural for grouping. "You can use an etagere singly or in multiples -- two or three together," says Williams. "That creates a nice rhythm with the style. And they nicely balance other pieces."

From slender frames of polished stainless steel combined with white oak, as in a 1970s-inspired Mitchell Gold and Bob Williams piece called Caffrey, which is distinguished by its asymmetrical shelving, to more traditional painted wood cabinetry embellished with fretwork, as in the Babette etageres from the HB Home collection for Kindel Furniture, there's a considerable diversity of style.

At French Heritage, the four-shelf Evry bookcase actually stretches to 62 1/2 inches wide. Part of the Avenue collection, the oversized etagere is architecturally elegant, with turned columns bisected by shelves with black edges and accents across the pediment top -- a pleasant contrast to its light blonde cherry.

Wall-mounted shelving with open backs, some with ladder-style shelves like the Helix from CB2 have a modern edge, especially with the teaming of oak with carbon steel in a graphic contrast.

Other wall-mounted shelving has graduated from the decorative ledges that have been popular for some time. Modular is back, but many of the cubes we're seeing are different from those popular in this country in the 1970s. Options allow you to configure in pleasing arrangements, sometimes in contrasting colors or finishes, with some systems, such as those from Ligne Roset, that complete the look with consoles -- i.e., cabinets with doors.

In addition, there are intriguing unorthodox shapes, such as the flexible design from Kartell called Bookworm. It, too, can be arranged as you like, from a snail-like spiral to an undulating curve stretched across a wall, nearly 27 feet in the largest size.

Circular frames also are adding to the mix. One called Bulls Eye from cFc, crafted from metal, houses conventional shelves. Lines, a bookshelf from Ligne Roset, is defined by what resembles a fat picture frame. Further distinguishing it are shelves that sit at angles, which sets up dynamic displays.

On the AllModern website, you'll find hexagon shapes that can be stacked (the Brant from Hokku designs), and one bookcase called Cloud from Cappellini that looks like conjoined bubbles.

Dimensional play also adds movement to some bookcases. Boogie Woogie, which comes in black and white as well as an arresting red, has an undulating surface that's reflective as well because of its high-gloss finish.

Some wall-mounted 3-D shelves read more like sculpture on the wall.

Curiously, a pair of low bookshelves from the manufacturer Julian Chichester, use flat shapes for the suggestion of sculpture. Inspired by classical, mid-century designs, the one sports simple quarter-sawn oak shelves that are divided by busts made out of gesso. The silhouettes depict Athena, the Greek goddess of love and beauty. Another version has pineapples with scored surfaces that pop against black limed oak shelves. Both seem whimsical and sophisticated at the same time.

You can always shake things up a bit with color. With more and more hues showing up in home design, it's no surprise that there are options for bookshelves as well. At Room and Board, there's Slim, delicately scaled powder-coated steel bookshelves available in 10 colors, including blossom (pink), ocean, green, navy, yellow and orange (five weeks by special order). The powder-coated natural steel bookshelf measures 24 inches wide by 15 inches deep and 72 inches tall.

Huppe offers color options (like bright yellow) to team with American walnut veneer for its Lyrics modules, which include open and closed storage, both wall-mounted and base pieces, making a variety of layouts possible.

Even larger entertainment systems are mixing up materials or finishes, as well as configuration, for more interest. At French Heritage, combinations of wood and metal can be rustic or modern in a Belgian industrial or loft look. The newest entertainment system at Habersham has a graceful arched pediment in the center, good proportions and cross-shaped boxes that create central focal points, and contrasting picture molding on the back panels.

Whether you prefer something streamlined or wall-mounted, symmetrical or off-balance, there are plenty of styles, materials, finishes and colors for bookshelves -- whether you have books or not.

Sources

-- All Modern, a division of Wayfair, 800-615-9703, www.allmodern.com

-- CB2, 800-606-6252, www.cb2.com

-- Chiasso, 877-244-2776, www.chiasso.com

-- Crate and Barrel, 800-967-6696, www.crateandbarrel.com

-- French Heritage, 800-245-0899, www.frenchheritage.com

-- Julian Chichester, 336-886-2454, www.julianchichester.com

-- Huppe, 819-758-1529, www.huppe.net

-- Kindel Furniture Company, 877-546-3351, www.kindelfurniture.com

-- Ligne Roset, 212-375-1036 in New York; check website for other locations, www.ligne-roset-usa.com

-- Noir Furniture, 310-527-5501, www.noirfurniturela.com

-- Room & Board, 800-301-9720, www.roomandboard.com

-- West Elm, 888-922-4119, www.westelm.com

-- Y Living, 800-236-9100, www.yliving.com