Stormwater management is directly related to sustainable development, with a clear impact on the quality of life of urban centres. While some countries have, already, become aware of its importance, producing legislation and implementing management solutions, in other regions the approach to the problem is still in a very early stage. Therefore, in this article an analysis of the legislation in force in the United States of America, in Europe and in Portugal is made as far as stormwater is concerned. It aims to present the main characteristics and differences, as well as the great opportunities inherent to a more efficient management of this resource. This study has shown that, unlike in the United States of America, both in the European Union and at a national level, there is no legislation supporting the importance of stormwater. This is a serious and potentially problematic situation, due to the great impact these waters have on the sustainability of the regions.