A chef poissonnier is the fish chef in the classical brigade, responsible for fish and seafood dishes and their sauces. The role requires expert fishmongery: filleting, portioning, and judging freshness by eye, smell, and touch, since fish deteriorates faster than any other protein. Cooking must be precise, as seconds separate succulent from overdone, across techniques from poaching and steaming to grilling and frying. The poissonnier also prepares fish stocks and classic sauces such as beurre blanc. With sustainability concerns reshaping menus, the role increasingly involves choosing responsible species and using the whole fish.