What’s a Dart Stitch?

If you design bags, this tiny fold can completely change their shape. It’s called a dart, a technique borrowed from clothing design. A triangle of fabric is pinched together and sewn, tapering from a wide opening down to nothing. Sew it shut and a flat piece of fabric becomes three-dimensional.

Designers use darts to add volume without adding another panel. Look for them on the bottom corners of bags, backpack lids and exterior pockets, where they make things pop outwards.

It looks like a tiny detail on the pattern, but it’s one of the simplest ways to turn a flat sheet of fabric into a three-dimensional form.