Business continuity refers to the capability of an enterprise to keep its core business functions and processes running during times of outages and disasters. Disaster recovery, on the other hand, refers to the upkeep of Information and Communications Technology (ICT) infrastructure of the enterprise, focusing on restoring this infrastructure as quickly as possible following any type of disastrous event. In this section, we will examine notions related to both these concepts. We will first discuss several terms related to the design of high-availability networks, after which we will examine reliability in power delivery and various recovery processes. Lastly, we will define a few common metrics related to these concepts.