The ability of bacteria to adapt their metabolism to nutrient limitation or environmental changes is essential for survival. The stringent response is a highly conserved mechanism that enables bacteria to respond to nutrient limitations. Central to stringent response is the synthesis of the nutritional alarmones pppGpp and ppGpp (collectively named: (p)ppGpp) that globally reprograms transcription and translation associated to variety of different cellular processes. In Bacillus subtilis and Staphylococcus aureus, three types of alarmone synthases (i.e., RelA, SAS1 and SAS2) have been identified that differ in length and domain composition. These differences might be attributed to their specific roles during stringent response. However, only little information on the molecular details is known. I will present our recent progress towards the structural/mechanistic understanding of the molecular framework of alarmone response.