Provided is an accessory mounting system for use in a cargo bed of a pickup truck. The accessory mounting system comprises a cargo hold assembly and at least one accessory member for releasable attachment to the cargo hold assembly. The at least one accessory member is configured to confer a cargo holding functionality to the cargo hold assembly. The cargo hold assembly includes a base configured to be mounted to a side-wall portion of the cargo bed. The base includes a plurality of registration bosses, each being configured to receive a corresponding registration cavity provided on the at least one accessory member. The at least one accessory member may be mountable upon the base in more than one orientation.