Coastal erosion along the São Paulo coast in Brazil has been studied since the 1980s. The researchers identified 11 indicators of erosion, with 17 causes, including natural processes and human activities. They measured shoreline retreat rates for six beaches over 56 years and assessed the risk of erosion based on the number and distribution of indicators. The results show high rates of shoreline retreat, even in non-urban areas, and indicate that natural factors play a significant role in erosion. These findings are important for managing coastal areas and developing rules for construction and activities near the shoreline.