Clinical symptoms alone at initial diagnosis, and during exacerbations of inflammatory bowel disease, offer incomplete understanding of the disease as under- and over estimation of disease activity can occur or key information be missed. Therefore, objective measures of disease activity are used to guide IBD treatment. Along with other routes of investigation, such as colonoscopy, cross-sectional imaging contributes significant data to our understanding of disease, which is important to evaluate for transmural treatment response and healing. The following chapter will focus on the available imaging options and propose an algorithm to guide the most appropriate use of these tools.