This is one half of the Business Continuity Plan and is directed specifically for Disaster Recovery Plan for your IT systems. Includes system analysis for risk, topology maps, impact analysis and back-up procedures review.
We have all come to rely on computers and the data they hold so much that not having a pre-thought out plan for recovery puts the chance of restoring IT operations quickly in the event of a crisis at a very low probability. How long could your company survive if you could not access your computer systems? If the answer to that question is less than a few days, then it is in your best interests to have a plan to get you operating as quickly as possible.