Joint reinforcement can be used to control cracking, tie masonry wythes together, boost structural performance, or serve any combination of these functions. With at least 10 different configurations of joint reinforcement, three principal types of corrosion protection, and two standard wire sizes to choose from, selecting the best product for a project can be a daunting task. For single-wythe walls there are three configurations of joint reinforcement: truss, ladder and seismic ladder. Since the 1950s, most multiwythe walls have been made up of a concrete block backup with a clay brick veneer or outer wythe. In this application, the joint reinforcement is used both to reinforce the block backup against shrinkage and to act as a wall tie connecting the outside brick wythe. Adjustable assemblies, truss- or ladder-type backups with eye and pintle or tab connectors, are the best choice for multiwythe walls. Regardless of the materials used in the wall, the sequence of construction, or the seismicity of the area, adjustable assemblies offer significant benefits.