This article aims to determine the law applicable to international contracts in the absence of choice by the parties. The article mainly focuses on the analysis of article 16 of the Chilean Civil Code in order to determine its correct meaning and scope, whereas it makes several criticisms of the positions that the doctrine and case law have traditionally adopted in this regard. After ascertaining the law applicable to the issues of both form and substance, the study focuses on determining how the connections set forth in article 16 should be materialized and then it ends by referring to the matters included within the scope of regulation of article 16.