SDA (Space Domain Awareness) and SSA (Space Situational Awareness – SSA) have been defined as comprehensive knowledge of space objects and the ability to track, understand, and predict their future location. The purpose of the article is to present SSA initiatives to protect space systems, which are now recognized as fundamental assets of the sustainable development of each country. The destruction of even a part of the space infrastructure can have severe consequences for the security of citizens and economic activity. These systems assume the combination of all data obtained by various entities operating in space and Earth to create a common database. The SSA system was created based on the US military programme SDA (Space Domain Awareness); SSA and SDA are almost similar, but SDA is a new term replacing SSA, which existed previously. SDA is a better and improved SSA. Increasingly, the SSA programme is part of national and EU space strategies, but it is not yet possible to include it in international space law.