CONTENTS Early Contractor Involvement in Dutch Infrastructure Development: Initial Experiences with Parallel Procedures for Planning And Procurement S. Lenferink, J. Arts, T. Tillema, M. van Valkenburg and R. Nijsten Environmental Impacts and the Most Economically Advantageous Tender in Public Procurement K. Parikka-Alhola and A. Nissinen Combinatorial Auctions in Public Procuremen…