For Performance Based Seismic Design (PBSD) applications, it is crucial to succeed in determining selected earthquake input groups characterized by a defined and specific probability of occurrence (Probabilistic Seismic Hazard Analysis - PSHA). The PSHA is generally performed by associating a probability of occurrence to a specific value of Intensity Measure and then by creating earthquake input bins characterized by that value. This paper presents a comprehensive methodology for the identification of groups of earthquake time history inputs associated to a specific hazard level to be used in the Probabilistic Seismic Demand Hazard Analysis (PSDHA) subtask of the PBSD procedure.