For nearly 30 years, the statutory provision, known as Nunn-McCurdy (NM), has been an oversight tool for Congress to hold the DoD accountable for cost growth on major defense programs. A NM breach occurs when a program's unit cost exceeds certain thresholds. When that happens, DoD must notify Congress of the breach. There are a number of statutory provisions that help implement cost growth reporting under NM. Referring to these statutory provisions as the NM process, this report examines trends in NM breaches and factors that may be responsible for these trends. It also discusses changes DoD is making or proposing to make to the NM process. Charts and tables. This is a print on demand report.