Cut the leafy ends off the bunch of celery.

Cut the stem end off the bunch. Wash the ribs of celery to remove any grit or dirt. Dry the ribs well.

Cut each rib in half to make the pieces more manageable.

Place one half of the rib down on the cutting board. Make a cut straight down. Repeat on the other side. Reserve these two cut pieces.

Remove the rounded top of the center piece to square the edges. Reserve the rounded top for stocks and sauces.

Cut the two straight sides and the square top into 1/8" thick strips.

This will leave you with matchstick shapes called julienne.

Cut the julienne into 1/8" cubes to make a dice called brunoise.

The useable pieces, left to right: leaves, scraps for stock and brunoise dice.