Cluster methodology
Cluster picking is a middle ground. The picker pushes a cart carrying several containers, one per order, and drops each pick straight into the container for its order. The orders are kept separate as they are picked, so there is no separate sorting step afterwards.
When it fits. Many small orders, like batch picking, but where you would rather keep orders apart during the pick than sort them out later.
Trade-off. It saves travel like batch picking and skips the sorting step, at the cost of the picker managing a cart of several containers at once.
A policy using cluster picking sets two extra fields: Cluster container count — how many containers (orders) ride on the cart at once — and Cluster container type — the kind of container used. See the wave picking policy for where these are configured.