PURPOSE: Animation deformities or breast distortion during pectoralis muscle contraction following subpectoral breast augmentation are a known entity, but its prevalence and significance remain unclear. The purpose of this study is to identify the incidence and severity of animation deformities as well as their effect on patient satisfaction and interference with certain activities. METHOD: All procedures were performed by the senior author using a variation of a previously described dual-plane technique. The first portion of this study is an evaluation of breast distortion by a group of independent observers in an unselected series of forty consecutive patients who underwent primary subpectoral breast augmentation. The second portion of the study was a questionnaire sent out to 195 consecutive patients asking about overall satisfaction, degree of animation deformity and whether there was interference with any activities. RESULTS: Of the forty patients' photographs that were evaluated, 9 (22.5%) had no distortion, 25 (62.5%) had minimal distortion, 4 (10%) had moderate distortion, and 2 (5%) had severe distortion. Out of the 195 questionnaires, there were 69 responses, a 35% response rate. 56 (82%) described mild to no distortion, 7 (10%) were moderate, and 5 (7%) were severe. According to the survey, the most common activities that were problematic were lifting weights and exercising (24% and 19%, respectively). Only one (1%) patient stated that she would not recommend subpectoral positioning. CONCLUSION: Although animation deformities do exist, nearly all patients in this study would still choose subpectoral positioning. Patients that may be better candidates for subglandular placement are those in whom exercise is central to their daily living. As a result of this study, surgeons and patients should have more accurate and reliable information regarding the significance of animation deformities after subpectoral breast augmentation.