As part of a broad effort to reduce defense expenditures, the Army is exploring a number of new approaches to training individual soldiers. Prominent among these approaches is "field-based crosstraining (FBCT)," which involves combining two or more occupational specialties and shifting initial skill training from Army schools to on-the-job training in field units. This report describes a method for analyzing the features, advantages, and disadvantages of field-based crosstraining programs in the Army. Focusing on the specific case of helicopter maintenance, the report analyzes data from field units and recommends alternative field-based crosstraining strategies for the Army. An assessment of the Army's Apprentice Mechanic Initiative (AMI) for helicopter maintenance is included in the analysis.