The contribution of company law to the realization of the domestic market is still pending in many areas. These findings were the starting point of the study in hand, which follows the central theme of company law conforming to a domestic market. This central theme has a legal and economic aspect: domestic market conformities in the legal sense are regulations relating to company law if they correspond to the compelling legal guidelines of Community law; in the economic sense they conform to the domestic market if they contribute to international trade in the domestic market. The clarification of the structural components, followed by the development of company law in the international process, takes center stage of the study, including civil rights, adjustments to the law, the creation of supranational legal forms and the concept of a legislator competition in the European domestic market. The findings gained are then applied to the current core questions of the European company law: the development of international company law, the protection of creditors and the systems of managing publicly owned firms.