The Mountain Rescue and Intervention Group (GREIM) of the Spanish Civil Guard plays a critical role in ensuring safety and conducting rescues in mountainous terrains. Established to address the specific demands of rescues in inaccessible and high-altitude areas, GREIM members require exceptional physical and technical preparation. This study provides a descriptive and comparative analysis of the GREIM admission tests, evaluating their rigor and comparing them to similar tests in other specialized rescue units. The primary aim of this research is to analyze the results of the GREIM admission tests and compare their type and level of demands with those of other rescue bodies and similar units. Data collection took place during the GREIM admission tests in March 2023. The GREIM tests are designed to select candidates with the necessary physical and technical skills to operate in extreme conditions. Compared to other specialized forces such as firemen and military units, the GREIM tests are more exhaustive, incorporating unique elements like climbing and navigation in difficult terrains. This ensures that GREIM members are prepared for the high physical demands of mountain rescues, where both physical and psychological resilience are critical. Overall, this study highlights the high level of physical and technical demand of the GREIM admission tests. The comprehensive preparation required for these tests underscores their alignment with the requirements of other specialized mountain rescue units internationally, ensuring the selection of highly capable and prepared candidates for mountain rescue operations. This comparative analysis reveals a convergence in the standards of these demanding assessments, adapted to the specific operational environments of each rescue unit.