Mikko Karikytö is the Head of Ericsson PSIRT, product security professional and a global force fighting evil and protecting the mobile subscribers. In his work Mikko is responsible of leading a headquarter based Ericsson PSIRT with global responsibilities including incident response and vulnerability management. More than 2.5 billion end-users use the services from which incidents originating Mikko and his gang are tasked to investigate. This talk is going be about Ericsson PSIRT and how it became a center piece on a network giant's dinner table. In my talk I will explain how a small team became so important and raised to the center of the corporate to guard the security of big part of global mobile networks. The networks that we all depend on, systems that keep us online regardless the location and time of day. Huge combination of technology generations and platforms that provide us services satisfying all our needs to be connected and social - to be human. This talk will shed light to the structures what a vendor like Ericsson builds to produce ever more secure networks and services, and how PSIRT is in very middle of all that. How PSIRT has grown from an incident response function to a central vulnerability management institution and even a governance function. A story of one vendor PSIRT that got to not only respond reactively, but also to proactively define and monitor the security assurance of an R&D giant. I will talk about challenges met on the way, sacrifices done and choices made. How the responsibilities have evolved, grown uncontrolled and shrank deliberately to maintain focus. My talk will cover challenges like how incident communication is tuned to fit the stakeholders in both ends of the same organization. How confidentiality of sensitive information is maintained while satisfying the need of sales and support to know it all. I will explain the maturity model, a framework that was created to bring all products on par in security and privacy, and what important role PSIRT plays in that machine. How in our model the lessons learned in PSIRT are infused to product and service development to make better, more secure, reliable networks. With great power comes great responsibility.