The international financial crisis and its impact on the international economy were the key drivers of a number of reforms in the regulation and supervision of the financial systems at the global level. In this context, various countries have developed an institutional and operational framework for macro-prudential policy implementation, aimed at promoting financial stability. In Portugal, the authority to implement macro-prudential policy was conferred upon Banco de Portugal. Therefore, the Bank is responsible for defining a strategy and the instruments to prevent systemic risks. This function implies analysing the risks deemed more relevant within the national financial system and selecting the appropriate instruments to prevent them. This article aims to contribute to this analysis: section 1 analyses the motivation underlying the definition of a macro-prudential policy strategy and the criteria to take into consideration when selecting its instruments; section 2 reviews the most relevant systemic risks within the national financial system; section 3 describes the appropriate instruments to prevent the various risks analysed; and section 4 concludes.