One of the most significant motivating factors associated with increasing automation in our networks is that of reliability. If we can increase the determinism in our network— through software regularly applying the same templates and processes—then we gain confidence and assurance in behavior through predictability and regularity. A network that behaves regularly is simpler to operate, easier to troubleshoot and generally easier to manage. But the other benefit that comes out of regularity and reduced complexity is improved security. In this chapter, we'll look at a series of recipes that help take some of the manual labour costs out of security-related tasks and procedures.