RPO (Recovery Point Objective): maximum acceptable data loss (how old can the backup be?).
RTO (Recovery Time Objective): maximum acceptable downtime (how fast must systems restore?).
RPO drives backup frequency: RPO = 1 hour → backup every hour. RTO drives recovery architecture: RTO = 15 min → hot standby needed. Lower RPO/RTO = higher cost. BIA identifies business-critical systems needing the lowest RPO/RTO. Document both for every critical system.