The article describes the main approaches to assessing multiplier effects from implementation of major international projects. A conventional example considers the distribution of effects between the supplying country and receiving country. Macroeconomic models have gained widespread acceptance in estimating multipliers for the whole economy in general (Beetsma, 2008; Christiano, 2011). Methods based on the input-output approach are typically applied for estimating effects at the industry level. Among these calculations, it is possible to distinguish three main types, which are as follows: (1) calculations within general equilibrium models with integrated input-output tables (Burfisher, 2017); (2) calculations within a static input-output model (Miller, 2009); (3) calculations within a modified input-output model using econometric dependences for modeling the impact of additional income on total consumption (Ghosh, 2011; West, 1995).