Gallery walls are a lot like Eames chairs and that one mirror from Anthropologie: They’ve been trendy for so long that it’s safe to say they’re not really a trend at all.

When you have a lot of art to display — or you just can’t decide which pieces to hang where — a salon-style gallery wall could be the answer. “It creates so much interest,” said the ...

But they’re a decorating staple, says Susan Tynan, founder and chief executive of Framebridge, an online framing company. “I get asked a lot whether I think the gallery wall trend will go away ...