Abnormalities of the alar base may be a consequence of base deformities, a secondary result of reduction of nasal base projection, or a consequence of maxillary abnormalities. A thorough clinical observation coupled with information procured from the analyzed lifesized photographs provides a consistent method for the evaluation of the alar base and the structures that affect its position. A critical step in choosing the surgical technique for correction is the classification of abnormalities. A systemic approach to such a classification is presented in this article and is accompanied by a description of the dynamic changes and optimal surgical procedures that would best benefit patients within each category.