The synthesis of 3,3'-azobis(6-amino-1,2,4,5-tetrazine) DAAT is described, obtained with an overall yield of 20% after six reaction steps. DAAT is a new high-nitrogen energetic material with remarkable thermal stability and insensitivity against friction and impact. DAAT decomposes at relatively high temperatures (> 250degreesC) releasing one of the highest heats of decomposition ever measured by DSC. The decomposition pathway and its products investigated by thermal analysis are described.