In synthesis, we must express that to talk of a contract legal stability we will refer to a contract public, in which administrative law and civil law elements coming together to produce consequences framed within the plans or State policies in an attempt to promote the growth and development of the economic unit. The basic model of stability contracts is none other than the contracts by accession, in which the contractual content has been determined with priority, by one of the Contracting Parties, the State, which must adhere, the co-contratante who want to formalize a compulsory legal relationship. The trait that marks the originality of the contractual mechanism is the commitment which assumes the State of your content keep invariable, without perhaps being able to use a legal norm for indirectly vary rules that are agreed. In this way, it has a latch that prevents the possibility mentioned above, therefore, in our legislation to exercise with, stability contracts have been extended in different sectors, while maintaining a uniform line and identical purposes. Projecting towards the end of the contract of stability, we will see that this will be one of juridical and economical character: from the point of view legal search give legal certainty to investors on the basis of the principles of certainty, trust, authorization, predictability and legality in State action; and on the economic side, its purpose is to become an instrument enabling the largest number of investments in the different sectors of the economy so that the structure economic macro mounted by the State, with a view to the revitalization and economic growth, is fed by productive capital and long-term that lead us to a collective development. A final check and it summarizes the analysis of this study has been the visualize what the political decision of the State is weighted as national economic predominant general interest through investments, mediating the firm conviction that it will be possible to encourage the process of economic revival.