Pathologic scarring affects millions of people worldwide with varying degrees of disfigurement, functional impairment, and psychosocial comorbidities. Over the past decades, several modalities have been devised to help assist in the evaluation of scar severity, progression, and response to treatment. In most cases, scars are assessed either with objective measuring devices, which provide quantitative measurements of physical scar features like pliability, firmness, color, and perfusion. Alternatively, patients and providers may provide more qualitative (i.e., subjective) assessments, which are largely observer dependent and address various other comorbidities such as pruritus, pain, and psychosocial sequelae. To date, however, there is no general agreement as to the gold standard tool(s) for scar evaluation. In this chapter, we provide an overview of the most common scar features assessed in fundamental research and clinical practice. We then discuss the basic clinimetric properties that should be considered when choosing an appropriate tool for scar assessments in order to prevent untrustworthy and invalid results. We conclude by describing the attributes and deficiencies of currently available scar-measuring devices and assessment scales, while also highlighting areas where further development is needed to better understand and treat pathologic scarring.