In this article, the author analyzes the implications of Kosovo's declaration of independence on state sovereignty and the principle of self-determination of peoples. He begins with an outline of the political process leading to the declaration of independence and the reactions of the international community thereto in which he also presents the various legal arguments raised for and against the lawfulness of Kosovo's secession from Serbia. The author continues with a discussion of whether the principle of self-determination of peoples does apply in the Kosovo case and whether the operation of this principle would justify a 'remedial secession'. Subsequently, he analyzes whether UN Security Council Resolution 1244 may be a legal barrier to Kosovo's independence to the extent that Serbia does not consent to such independence. Finally, in view of the extensive powers vested in the new international presence following Kosovo's declaration of independence, he discusses whether Kosovo fulfills the criteria of effective government and independence for being a state under general international law. The author concludes that international law remains controversial as to questions pertaining to conflicts between state sovereignty and self-determination of peoples and particularly to 'remedial secession', and that it is still too early to determine the impact of the Kosovo case on the development of international law.