Too Big: Traditional styling isn’t this wing chair’s problem. Proportion is. The high back is stately, but it overpowers the lower-back sofa, which should be the room’s dominant piece. The dark caramel color also dominates the room’s other furnishings. The result: This chair’s massive scale diminishes everything around it.

Too Small: This small chair proves that there’s more to scale than height. Sure, it’s too short in proportion to the sofa. But a razor-thin back, reedy legs, and paper-width sides also contribute to the chair’s diminutive look. Although the blond rattan matches the pine benches and the pale upholstery connects to the light-colored walls, even these work as a negative: The chair’s light palette accentuates its skinny scale.

Too Large: Bigger isn’t always better. This coffee table’s well-chosen style can’t compensate for its overscaled size. Nearly as long and as wide as the sofa, it competes rather than complements. It leaves no room for traffic flow and no space for stretching your legs out on the floor. Even the tabletop array looks lonely.

Too Small: This miniscule table not only looks out of proportion, it functions poorly as well. Those seated at either end of the sofa would have to do some serious stretching to grab a handful of popcorn or retrieve a book. Also, because the table is so small, its surface is nearly covered with accessories. There’s little room left for a coaster and cup, much less a spot to prop your feet. Tables spanning only one-third of the sofa length are too small and will throw the grouping off balance.

Too Tall: Used as an end table, this wood pedestal towers over the sofa, making the sofa appear small and the pairing awkward. And: Elbows beware! Anyone seated should keep funny bones away from these corners. The pedestal has a formal, traditional style that doesn’t suit the style of the sofa. A softly padded and rolled arm such as this begs for an equally casual — even rustic — end table.

Too Short: Although this table offers bonus function with its two drop leaves, it is not the right match for this sofa. The lamp would need to be fully stretched to offer good illumination from this low point. And anyone seated on the sofa would have to reach out and around the front of the sofa arm to access items on the table. The table would be better situated in front of the sofa.

Just Right: If you’ve ever bumped your elbow or dropped a teacup in midair, you know the annoyance of an end table that is the wrong height. The perfect pairing, visually and physically, is a tabletop that is a couple of inches shorter than the sofa arm.

Wallpaper

Too Big: The large-scale motif and strong colors of this floral wallpaper overpower the petite powder room as well as the fixtures and furniture in it. If you’re using an oversize pattern in a small space, choose one with more subtle color contrast. For instance, if this wallpaper had a pale blue background instead of cream, the pattern wouldn’t seem as busy. Control clutter by minimizing accessories and keeping them bold in scale and simple in style.

Too Small: Smaller in scale and lighter in color, this blue-and-white miniprint isn’t really wrong for the space. In fact, the soft colors and the predominance of white in the wallpaper, the sink, even the side chair — can be quite soothing. Still, the overall impression is ho-hum, primarily because the pattern is so small and pale that it almost disappears. A small print with more color contrast or a colored background would have greater impact.

Too Big: Visually connecting the furnishings is one thing, but swallowing them up is another. This rug covers too much of the floor beyond the conversation area to define it as a discrete space. Intimacy is lost, and, because the rug has become a dominant feature in the room, so is its value as an accent. Tip: Leave enough exposed floor around the area rug for the rug to work as an accent. This also allows the rug to complement the furnishings without overwhelming them.

Too Small: Ideally, this braided rug should knit the sofa, rocking chair, and cocktail table into one intimate grouping. But even the cocktail table isn’t fully grounded by this pint-size piece. Instead of creating intimacy, the rug only increases the appearance of isolation.

Just Right: To define a conversation area and create intimacy, choose an area rug that’s about as long and wide as the furnishings in the space. This area rug is just right because it spans the length of the sofa and the width of the rocking chair. Also, it is big enough to accommodate all four legs of the cocktail table — a must.

Mantels

Too Little: Though the idea of bracketing a larger item with smaller ones isn’t necessarily bad, the result here isn’t inspired. Set squarely in the center of the mantel, the large picture seems to shoulder aside the much smaller items, throwing the arrangement out of balance. Too much space between objects makes the candlesticks and the too-small frame look lonely, the bare wall yawning above.

Too Much: Each object to the left of the large picture has a corresponding object to the right, but the effect is overload rather than balance. The eye bounces from side to side, pairing items, instead of moving smoothly through the grouping. There’s no time to pause to consider any single object, since they are all stepping on one another’s toes in a jostle for space.

Just Right: Shifting the large picture in this arrangement to the left creates a fulcrum that is pleasantly off-center. The picture’s height deftly balances the relative weight of the flowers and rounded pitchers. A smaller framed mirror repeats the larger frame’s shape and finishes off one side of the display. With the weight now shifted to the left side, fewer items are needed there for balance: The urn echoes the simple shapes of the pitchers. Overlapping the small frame and candlestick leads the eye gracefully back to the center.

Art

Too Big: There’s no breathing room in this art-to-sofa match. By exactly spanning the sofa’s width and exceeding its height, the picture competes with the sofa instead of supporting it. The result is overpowering. The color balance is off, too: The print’s pastels are too pale to connect easily with the primary-colored pillows.

Too Little: This picture is tall enough, roughly matching the height of the sofa. But it ends up looking leggy and lost because it’s too skinny in proportion to the sofa’s width. If you’re in love with a piece of art that’s too small for the spot where you want to hang it, try beefing it up by adding smaller items. In this case, adding a second similar-size print and centering the two, or balancing this one with two narrow items on either side, would correct the scale.

Too Big: Though graceful in shape, this tall lamp towers above the nearby sofa and chair. It is also several inches taller than the table it rests on, throwing off the balance there as well. Finally, this lamp is too tall to provide optimal reading light: When seated you can see the bulb, which casts an annoying glare.

Too Small: This petite porcelain lamp is overwhelmed by the high-back sofa and stocky chair that surround it. Because of its small scale, the lamp also functions less than adequately, since optimum reading light comes from slightly above eye level.

Too Big: Lighting a tabletop is one thing; flooding it is another. This 5-foot-wide double pendant chandelier overpowers the table. The dark shades also add visual weight, making the light appear top-heavy. The straight lines of the fixture make it look even longer than it is.

Too Small: The style of this simple pendant lamp complements the understated table and chairs. But the fixture is too small to adequately light the table. If you prefer a pendant style, try placing two over a rectangular table. (Keep in mind the general rule that chandelier width should be less than table length.) A better choice for this single fixture would be a round table with a relatively small diameter.