A number of PPP projects have been announced recently in Greece introducing a new procurement method in the projects covering public needs. The aim of the present report is to present the strategy adopted by the majority of medium sized companies foreseeing in bidding such projects. The risks and the uncertainty of the PPPs led the firms to hesitate on participating on alone bidders and strategic alliances came as the solution. Moreover, the absence of knowledge on past infrastructure projects under the umbrella of PPPs was a subject of significant importance. Therefore, the strategy should be used as the mean to surpass the unfamiliarity with the PPPs while the rest of the bidders have already had experience. The partners in the strategic alliances were chosen carefully by the participating firms with the main characteristic being the repeated ties between them. So, they introduced the implementation of trust as their mean to overcome the barriers for entry in the field of the PPPs. Relational contracting is the concept that the firms used as their criterion for choosing partners. Key words: PPPs, medium sized companies, strategic alliances, relational contracting, trust Word
