»The Equalization of Accrued Gain in the System of German Family Inheritance Tax Law. National and International Principles of Taxation«: The majority of spouses in Germany live in a legal or modified community of accrued gains. This is the most economically viable matrimonial property regime, as transfers of assets for the purpose of equalizing gains are possible without incurring German inheritance and gift tax. This seems simple, but the aim of the scheme itself raises numerous questions. This work is the first to examine the central provision of sec. 5 German Inheritance Tax Act at the intersection of German constitutional, civil, and inheritance tax law. In addition, the work addresses, on a comparative law basis, the equally important question of how foreign property regimes are to be assessed within the scope of the provision.