Crash retrieval and reverse engineering is the claim that governments have recovered vehicles, debris, or biological material of non-human origin and placed them in secret exploitation programs. The idea joins two activities that are real in ordinary defense work—collecting foreign hardware and analyzing it—with a much more consequential allegation about anomalous technology. Public discussion often reaches back to Roswell, but recent attention centers on testimony about a hidden U.S. program operating outside normal congressional oversight.

The most prominent modern source is David Grusch, a former intelligence officer who told Congress in 2023 that he had been informed of a multi-decade retrieval and reverse-engineering effort. He said his account drew on interviews with people who claimed direct access, while also distinguishing what he personally witnessed from what others reported to him. Other former officials have offered supporting statements of varying specificity. No publicly released craft, laboratory record, or biological sample has yet enabled independent confirmation of the central allegation.

Official reviews dispute it. The All-domain Anomaly Resolution Office reported that interviews and archival research did not substantiate a hidden extraterrestrial technology program; it said several stories were misinterpretations of authentic classified national-security projects or repeated accounts without verifiable evidence. Critics argue that compartmentation and access barriers could limit such a review. That disagreement makes documentation, access, provenance, and first-hand status more important than the number of times a story is repeated.

The subject overlaps with the alleged Legacy UFO Program, special-access controls, contractor custody, and proposed disclosure law. It should be separated from confirmed foreign-materiel exploitation, which does not establish an anomalous origin. At present the public record supports the existence of serious allegations, protected testimony, and official investigations; it does not publicly demonstrate possession of non-human hardware or a successful reverse-engineering program.