This report analyzes the training resources needed for future postmobilization training of combat brigades in the Army National Guard. It lays out a detailed 102-day postmobilization model for an "enhanced readiness" heavy brigade, seeking to minimize train-up time by executing many activities in parallel. It then analyzes the key resources required (active trainers, gunnery and maneuver sites, and Opposing Force personnel) to prepare the brigades for deployment, under various options involving multiple training sites. It concludes that under current plans, the Army will have sufficient training personnel and other resources to run three training sites simultaneously, assuming that the National Guard can provide an Opposing Force, training support personnel, and garrison support for collective training sites. The sites would also need some equipment enhancements, such as additional MILES laser training systems and visual modification of tracked vehicles. This would produce as many as three trained brigades as early as 108 days after mobilization. To run more sites (and hence produce more brigades during the early phases of a deployment), the Army would need more active training personnel to oversee training and to provide OPFOR cadres at the extra sites.