This paper aims at putting forward view points regarding the use of stability technology to prevent and control cascading outages by examining recent black out events. Basedon the inquiry reports of the 2011 Southwest America blackout and the 2012 India power blackouts, event evolution featuresare first summarized from a stability perspective. Then acomparative analysis is conducted so as to propose suggestions of effective measures, either preventive or emergency, which could have avoided the blackouts. It is shown that applications of several mature technologies can create opportunities of preventing or interrupting the cascading development. These include offline dynamic simulation, online stability analysis and preventive control, real-time situational awareness and automatic emergency control. Further R & D directions aregiven to address the challenges of modern power systems aswell. They cover system fault identification criterion of pro-tection and control devices, verification of adaptability ofcontrol effect to system operating conditions, real-time oper-ational management of emergency control measures and improvement of simulation accuracy.