International Investment Agreements in Contemporary Practice: Legal Nature and Key Models

The article systematizes the principal contractual models used to structure international investment relations in contemporary practice and clarifies their legal nature with due regard to the interplay between private-law and public-law elements. It argues that the stability of an investment regime depends not only on contractual clauses as such, but also on legal certainty, the quality of legal drafting, and the consistency of law enforcement, including the predictability of official positions taken by public authorities. The paper demonstrates that different categories of investment agreements vary in the allocation of commercial and sovereign risks, the degree of state involvement, and the mechanisms of project control, which in turn affects the effectiveness of legal safeguards and the enforceability of undertaken obligations. General conclusions are offered on the importance of coherent regulation and consistent application of law for strengthening trust in investment relations and enhancing the resilience of cross-border projects.