The blue shield is the distinctive emblem used in armed conflict to indicate that the marked property is entitled to protection as cultural property under international humanitarian law. Determining which property should be marked with the distinctive emblem is the responsibility of the State. No further guidance is included in the international legal requirements on what to consider in making this determination, however. This report outlines the legal framework applicable to marking cultural property as protected in armed conflict. It analyses the relationship between these rules and other areas of international law that protect cultural property, including the UNESCO World Heritage Convention. The report investigates if property can be marked as cultural property and identifies relevant factors for deciding whether cultural property should be marked or not, taking into account the uniqueness of certain cultural property in Sweden. The identified factors to consider are: the aim of the 1954 Hague Convention; the cultural property's geographical location; the current use of the property and by whom; the adversary's military strategy; the context; and other factors relevant to the cultural property. Marking cultural property with the distinctive emblem aims to facilitate identification of protected property under international humanitarian law. This is as relevant today as it was when the 1954 Hague Convention on Cultural Property was negotiated, and a key tool in ensuring this protection for the benefit of all humankind.