Fiscal vulnerability and sustainability issues in emerging market countries.

Summary The objective of this thesis is to better understand the determinants of sovereign risk and fiscal sustainability in emerging countries, in order to identify the elements that would allow these countries to protect themselves from such risk. We implement econometric and theoretical tools adapted to the specificities of these countries. These tools are then used to try to anticipate episodes of severe sovereign default via a regime change model of the "early warning" type, to carry out stochastic simulations of the sovereign debt ratio in the medium term and to evaluate the effects of fiscal policies defined at this horizon and finally, to characterize the distribution of the external debt ratio of these countries. This thesis intends to identify the countries that seem to be the most exposed to sovereign risk and to define policy recommendations that take into account the heterogeneity within the "bloc" of emerging countries and over time.