As the sophistication and complexity of modern products advances forward, the approach towards cybersecurity and safety has to evolve as well. This presentation will discuss the difficulties in analyzing threats for big systems such as operating systems, cloud infrastructures, and automobiles. We will propose ways, guidelines and techniques to perform a Threat Model at large scale as part of the Security Development Lifecycle (SDL) – Understanding the key elements of a system, its threats and assets Before jumping into code audits & fuzzing.