Unification, or uniformity of transport law is a primary objective to many international organizations founded with that purpose. Transport law is branched in numerous fields of law such as air transport, road transport, railroad transport, maritime transport law and inland navigation . Each of these branches has its specifics because of which each branch represents an independent field of law, but in certain segments they have a lot of common ground, thus there are international sources of transport law as a whole (for all or several branches of transport) and international sources of transport law with significance or appliance to a certain transport branch.Transport, as such, represents service of transfer of people, goods, energy and information from a certain area to its destination. In wider terms, it includes transport as a transfer of people, goods or commodities and communication as a transfer of news, images and other information. National transport law regulation is of significant importance to performing transport within a state, but when it comes to transport between states there is a need of applying equal rules for all states involved. Thereby more economical transport of passengers and goods is ensured. Transport policies' are of the most importance, since the economy's growth, capital investments, transport technologies development, supply and demand relations, and environmental issues are very much dependent on them. Some of the most important international organizations which have contributed to unification of transport law to all branches of transport, and related international agreements have been mentioned in this thesis, along with conventions which are results of interstate agreements, which regulate relations among parties in international transport. First international conventions have been passed in maritime transport, followed with air, road and railroad transport conventions. In addition, in this thesis there is a point of relevance of international agreements and conventions and inclusion of states in the process in order to provide rights and security in transport, along with contributing to development of rights in specific branches of transport law.