Scientific analysis of headstart effectiveness has generated powerful basic biology that applies to augmenting tortoise populations that are on the cusp of minimum viable densities. Committing to evaluating headstart effectiveness requires long-term commitments of resources for long-lived, late-maturing species like desert tortoises, but enables assessments of fundamental vital rates, growth rates, and variables influencing them, to enhance effectiveness of headstart techniques. These programs also provide opportunities for serendipitous findings in basic and applied biology. The tortoise headstart program for the Marine Corps Air Ground Combat Center, Twentynine Palms California, has successfully produced 475 hatchlings and released 234 juveniles with hard shells, which improve resistance to predators such as common ravens. More releases will ensue. Headstarting has improved stock of juveniles (ten years old) to ten times that would occur in the wild, and released tortoises are being monitored for their survival, growth and long-term success post release.