The chapter presents the results on the performance of the SASMEX during the 2017 earthquakes that hit Mexico City. The approach has been the use of a questionnaire-based survey to a sample population of N=2,400. The results are discussed in the context of a systemic disaster management system (SDMS) model. A summary of the key findings are: 1) for the 07 September earthquake, age and occupation were significantly associated with the performance of the SASMEX system, to the extent that young (13-20 years old) participants considered the early warning system as very useful; however, employees considered it as “not at all” useful; 2) for the 19 September earthquake, age and occupation were significantly associated with the SASMEX performance. In particular, the subjects in the over-50 range considered the system as “not at all” useful, and students and employees regarded it as “very useful”; 3) given 1 and 2, it is necessary to further educate the residents of the capital city on the functioning of the SASMEX system (e.g., its strengths and weaknesses, warning time, etc.).