The present study deals with possibilities and limits of contracts under private law in Austrian administrative law
and describes problems associated with it in the light of contractual spatial planning. The frequently improper
implementation of regional planning charts shows that acts of sovereignty alone cannot insure the realization of
objectives required by public interest. It is therefore necessary to set up contracts under private law in addititon to
measures of sovereignty. The example of town planning contracts in Germany illustrates, how wide a range of
applications contracts of public and private law offer. The fact that Austria lacks a system of administrative
tribunals, that have full jurisdiction, suggests the use of contracts under private law for the accomplishment of
public tasks.
The greater acceptance of co-operative ways of acting, as well as the substancially extended possibilities of
arrangement compared to unilateral acts of state, and agreements on additional benefit above codified law are
undisputable advantages of this type of contract. Opposite to this are well-founded concerns such as the lacking
parity of the contracting parties, the absence of public contractual liberty, as well as the danger of overreaching the
citizen in consequence of the junction between acts of sovereignty and contracts. The aim of this study is to weigh
benefits and drawbacks of contracts against each other and to point out constitutional and other legal guidelines for
administrative actions under private law. Fundamentals of competence will be discussed as well as the extent of
legal obligations of the state subject to private law, its obligations towards constitutional rights, and the guarantee
of legal protection for the citizens concerned. Further, we will investigate whether planning considerations are
structurally different from other forms of administrative discretion. At the center lies the answer to the question, to
what extent the choice of legal forms is admissible, and in which ways regional planning charts, qualified as
decrees, may be connected with petitions, manifestations of intent, and contracts.
In addition, problems regarding exact structure and consequences of defect of contracts will be discussed. Another
objective of this study is to find overlapping principles of law, which are equally valid under public and private
law, and which can therefore contribute to a harmonization of both of these vast fields. The increasing interlocking
between public and private law, as well as the blurring of the borders between state and society challenge - not
least over the background of European law - the traditional dualism and justify the assumption that there exists no
sharp contrast between these two fields of law, but that there are merely traditionally defined core regions with
floating transitions. Under these aspects, a modern administrative law should no longer refrain from the
implementation of actions under private law.