A public tender is the process through which the Greek State agencies request from economic operators the supply of goods and services as well as the implementation of public projects. The procedure followed is initially the publication of the public tender by the contracting authority stating in detail all the specifications of the supply, service or project, then the collection of offers from economic operators and finally the selection of the best offer based on the specific criteria it has set the contracting authority. Depending on the type of procedure chosen by the contracting authority, the criteria and the way of conducting the tender may differ based on Law.