35.1 Introduction

Contract law in all countries is based on the twin principles of freedom of contract, and pacta sunt servanda .2 However, each jurisdiction has laws that impact on contracts for construction work. Local laws apply if the governing law of the contract is in the jurisdiction, if the site of the construction work is in the jurisdiction or if the seat of dispute resolution is in the jurisdiction. This chapter explores the question of whether there are universally accepted principles of construction law, a lex constructionis, or whether it is trumped in every jurisdiction by local laws that differ from international norms. Three issues are discussed that support the concept of lex constructionis in the international practice of construction law: the use of FIDIC contracts, international commercial arbitration and the lex mercatoria.