Smart devices are all around us nowadays. These little angels/devils are making our lives much easier, while also opening up a lot of security/safety holes, esp. those safety critical devices have the potential of physically harming or even killing us. In this NIS lecture, in order to demonstrate the real threats of these devices, I will use a case study of a software intensive medical device ‹ the Insulin Pump ‹ from one of our previous projects at the McMaster Centre for Software Certification, McMaster University, Canada. Based on the insulin pump example, I will give an overview and discuss some important aspects of the key approach to make these systems safer and more secure: software certification.