The maritime zones of Russian Federation overlap with those of 12 neighbouring states. The practice of the Russian Federation concerning the delimitation of the boundaries of these zones provides an interesting opportunity to analyse the role of international law in the policy of a state in this respect, especially because bilateral negotiations of the Russian Federation have raised complex issues of law and fact. The analysis suggests that international law may influence the policy of a state regarding the delimitation of its maritime zones in different, albeit limited, ways. The role of international law in bilateral negotiations supports the conclusions the case law has reached on the significance of bilateral delimitation treaties for the formation of customary international law. This first part of the article provides an outline of the contents of maritime delimitation law, and analyses general aspects of the Russian Federation's practice concerning the boundaries of its maritime zones and the delimitations with Estonia, Finland, Georgia, Japan, Lithuania, North Korea, Poland, Romania, Sweden, Turkey and Ukraine.