For courier shipments you do not need to provide a broker. The courier will act as your broker. On certain Express shipments (DHL & FedEx), the brokerage charges are included in the cost of shipping.
For LTL shipments you will be required to provide your own broker.
For LTL shipments into the US from Canada or vise versa, you will need to have a dual broker that will be able to broker customs for both US and Canada.