With the evolving geopolitical situation and Sweden´s recent NATO integration, the understanding of Host nation supports multifaceted role is increasingly vital. Previous research lacks a theory regarding host nation support. The purpose of this thesis is to seek a better understanding on host nation support and to initiate a theoretical framework on the subject. By employing a method of hypothetical deductive approach, the study analyzes identified factors such as deterrence, planning, transit, infrastructure, and civil support. The factors were identified from previous research and motivated with theories from military science and the authors reasoning. The theoretical framework has it´s grounds in the authors reasoning that deterrence is the purpose of host nation support and the other factors are contributory to it. The analysis centers on the cases Operation Desert Shield and Operation Desert Storm during the Gulf war. The result confirms various of the factors contribution to the deterrence in host nation support in the specific cases and that there are complementary factors involved also.