"As a general rule, an end table within 1-3 inches of your sofa or chair’s arm height produces a harmonious look, and it is very hard to go wrong with this proportion," says Kuo. Of course, there are exceptions to this rule, depending on the height of your sofa. Kuo also says it's worth considering what you want to put on your end table when you think of height. If you plan to put a lamp on your side table, she says that the bottom of a lampshade shouldn’t be above eye level for a person seated on a chair or sofa. "Finally, for a truly balanced design, you’ll want the depth of the end table to be equal to or less than the depth of the sofa or chair its accompanying," she adds.