Pain is the most common motive for the need to undergo rehabilitation treatment and the measurement of this symptom helps to understand the patient, evaluate the evolution of their disease, monitor the effectiveness of the therapy while, within the individual rehabilitation project, it serves as a measure of the final outcome of the rehabilitation team’s work. This article examines the different modalities for measuring pain, which can be focused on estimating its intensity or on characterizing its features. In addition, a new application for portable devices is presented consisting of a minimal data set for the measurement of pain in rehabilitation.