Results of separation of the same feed into products can be evaluated by different procedures. Relatively well known are product-separation, upgrading, and classification. The procedure of product separation relies on determination of the mass or yield of products, upgrading is based on determination of mass or concentration of a feed component (chemical component, particle, fraction) in products while classification relies on analytical determination of content of various fractions present in the feed and products and takes into account the value of the feature responsible for separation. In this paper another approach is described, which was named sorting. This procedure utilizes the results of analysis of the quality of separation products and the feed based on the determination of the value of the property utilized for separation (or related feature) of individual particles (or a group of particles) and assigning it to different sorting groups of similar properties. The sorting curves are plotted as a selected separation parameter versus the group number. There are many sorting-separation parameters including contents, yields, and their combinations. The simplest parameter of sorting is probably the recovery of a group of particles, which provides sorting curves similar to the Tromp curve used in classification. The separation results can be plotted either in a form of two lines, one line, or a point. However, a meaningful comparison of the separation results by means of sorting curves is possible when the separation tests are performed for a given feed quality and given magnitude of ordering forces while the position of the splitting forces changes. A family of sorting curves can be obtained for tests performed at different levels of the ordering forces.