The aim of this paper is to briefly describe concern contracts. In view of dynamic development of economic relations, there is a variety of contractual relations. The first part of the paper analyzes the causes of making corporations. Article describes internal and external economic objectives, contributing to the formation of koncernowych structures. Economic factors like development of enterprises result to concentration of capital within the framework of concern. The second part of the paper refers to division of concern contracts on vertical concern contracts and horizontal concern contracts. Content both type of contracts is analyzed with special regard into german law. Elaboration in next part presents character of concern contracts. It takes consideration in problem with residual polish regulation of concern contracts, included article 7 Code of Commercial Companies. In Poland concern contract is an unspecified agreement, meaning that it is not regulated by any legal act. The summary of the paper, based on the analysis of concern contracts, presents conclusions to form legal relations based on the principle of freedom of contract, favouring development of entrepreneurs. Considerations at this point lead to the conclusion that not every innominate contract is of a transitory nature. Certain innominate contracts are of a permanent nature and there is no need to put them in the statutory framework. Evolution of the economy leads to creation of new needs of entrepreneurs, for whom it is more convenient to be able to form binding relationship in a flexible way, which is in turn possible thanks to the freedom to contract.