Over the last few years, an increasing body of work has documented observations, model simulations, and theories for the dynamical drivers of the ITCZ location and how it can change. More recently, a small number of studies have begun to focus on the ITCZ width as well. In this review paper, we synthesize this recent work, with a particular emphasis on the newly emerging work on ITCZ width and its changes. We also present new analysis of the changes in ITCZ width and strength in CMIP5 model simulations. We show that changes in ITCZ width and strength are tightly correlated across CMIP5 model simulations, and present a scaling equation to quantify this relationship. This work will frame future efforts to understand the relationship between width and strength change, as well as their influence on general circulation.