Agile software development is the methodology of choice for software shops today. But there are still organisations which are not practicing Agile in their software development, who might be interested in adopting DevOps.
When I say Agile Software Development, I mean any offspring that came out of the Manifesto for Agile Software Development. Such as Extreme Programming, Scrum, Lean Software Development and others.
Is Agile software development a mandatory prerequisite of adopting DevOps on an organisation level?