The article gives a thorough analysis of various means of regulation of trans-border private law issues, including trans-border construction activities, based on a contract. The author analyses the sources of law, applicable in the sphere of construction, their types and specific areas of application with regard to practice. Analysing the sources of international and national law, the author comes to the conclusion that it is necessary to take into account their specifics and development tendencies when drafting cross-border construction contracts. The author compares international and national sources of law, types of regulation at conventional and national levels and comes to the conclusion that the conventional and national sources of law are closely interconnected. Private international law; standard form contracts; construction contract; lex mercatoria; construction activity regulation, international convention, conventional regulation, conflict of laws, foreign trade transactions, standard contracts; contract, building contract; lex mercatoria; regulation of construction activities.