The National Institute for Discovery Science (NIDS) was a privately funded research organization in Las Vegas, Nevada, founded in 1995 by real-estate and aerospace entrepreneur Robert Bigelow. It described itself as a science institute studying aerial phenomena, animal mutilations and related anomalies, with a stated interest in phenomena that appear to be under intelligent guidance. Bigelow placed it in inactive status in October 2004, but its people, methods and Utah ranch carried over into the Pentagon-funded study he ran a few years later.

The institute's 2001 staff list named Bigelow as president and founder, biochemist Colm Kelleher as deputy administrator, retired Army colonel John B. Alexander as a project scout and physicist Eric Davis as its aerospace physics specialist. A science advisory board chaired by physicist Harold Puthoff included Apollo 14 astronaut Edgar Mitchell, computer scientist and ufologist Jacques Vallée, statistician Jessica Utts and John Schuessler. NIDS asked the public for reports of sightings, close encounters and unexplained cattle deaths, promising confidentiality and free laboratory analysis of physical evidence, and it paired former law-enforcement investigators with contract veterinary, biological and materials laboratories.

Cattle mutilations were a central focus. Kelleher has described a national network of ranchers, police and veterinarians meant to get investigators to carcasses before decomposition destroyed evidence. A hotline opened in 1999 drew more than 5,000 phone and email reports, many of which were explained as missile launches and meteors, and the institute attributed black-triangle sightings to secret advanced military aircraft. In 1996 Bigelow bought Skinwalker Ranch in Utah's Uintah Basin from a family that had reported strange lights and dead cattle, and NIDS made it a monitored research site.

Kelleher and journalist George Knapp later wrote in Hunt for the Skinwalker (2005) that the team saw or investigated close to 100 incidents on the property, though the investigators acknowledged difficulty obtaining evidence fit for scientific publication, and skeptic Robert Sheaffer has called the phenomena almost certainly illusory. Bigelow's October 2004 notice said NIDS had not needed to do major investigative work for more than two years and that Kelleher had left Nevada for cancer research. The book later drew Defense Intelligence Agency analyst James Lacatski to the ranch, a contact that led in 2008 to AAWSAP, contracted to another Bigelow company.

NIDS remained a reference point in 2026 as its veterans returned to public view. On the Bigelow Podcast, Bigelow and current ranch owner Brandon Fugal compared the NIDS years with Fugal's instrumented investigation, and Kelleher revisited the mutilation network on the Weaponized podcast. Davis said in a July 2026 interview that he had seen photographs of a dead non-human being from a Cold War-era foreign crash retrieval, a claim he attributes to classified intelligence that has not been released. The institute's lasting significance is as the private precursor to AAWSAP, supplying the program's ranch, several of its key people and its approach to anomaly investigation.