Drone-assisted SAR is a modern investigative technique that uses unmanned aircraft systems (UAS) to fly pre-programmed grids over a search area, enabling the capture of thousands of high-resolution photographs. In Lankford’s book, this method is presented as vital in several cases. Due to the limitations of software analysis at the time of Lankford’s search, the process depended on human volunteers known as “image squinters” to meticulously review the photographs for clues. As the author notes, the pilots “called these people ‘squinters’ because they spent hours squinting at photographs on a large computer or television screen, looking for signs of missing people” (133). This human-centric approach, justified by a Purdue University study quoted by Lankford showing that people outperform software in this task, led directly to the successful recoveries of missing hiker Paul Miller in Joshua Tree National Park and Rosario Garcia in the San Jacinto Mountains. The success of these searches establishes a replicable model for civilian-led efforts, though scaling it requires a network of trained pilots, dedicated squinters, institutional permissions, and funding.

A hiker box is a common feature of thru-hiker culture, serving as an informal swap meet at hostels, post offices, and other trail hubs where hikers can leave surplus food and gear or take items they need. The general ethos is “leave a little, take a little” (97). The memoir explores the hiker box as representative of trail culture, especially its communal ethos. The hiker box at Mike’s Place is a significant source of evidence in Lankford’s search for Chris Sylvia after another hiker reported seeing items later confirmed to have belonged to Chris. This discovery was a crucial clue, suggesting Chris had intentionally shed his possessions before disappearing. The fact that official searchers initially overlooked these items links to the theme of Citizens Filling Institutional Gaps.

The Koester Model is a statistical approach to SAR that uses a database of over 50,000 resolved cases to predict where and how different types of lost individuals are most likely to be found. Developed by Dr. Robert J. Koester, this framework provides an empirical baseline that helps search planners prioritize areas and temper intuitive hunches with data-driven probabilities. Koester’s work offers specific guidance, advising planners to “never abandon the statistical search” by ensuring statistically likely areas are covered (108). Lankford applies the Koester Model in her SAR practice, and the book highlights the usefulness of its data in her investigations. For example, the knowledge that 95% of lost adult hikers are found within 11 miles of their last known point helped Lankford define the initial search radius for David O’Sullivan. Similarly, the statistic that 75% of stranded motorists are found within 2.8 miles of their vehicle informed the successful search for John Sturkie. The model also reveals counterintuitive patterns that Lankford explores, such as the fact that solo male hikers have a higher fatality rate than solo females, providing a critical analytical tool for search managers.

Search theory provides the formally established methodology and vocabulary for planning and managing a SAR operation, used by professional searchers. As Lankford explains this, the process begins by establishing the subject’s Point Last Seen (PLS), which is “the last credible sighting of a missing person,” and Last Known Point (LKP), defined as “the last place where a missing person left behind physical evidence” (106). This information is used to determine an Initial Planning Point (IPP) from which to launch the search. From the IPP, planners establish a “containment” boundary to prevent the subject from moving into the “Rest of the World” (ROW), the unsearched area beyond this initial focus. To monitor these boundaries, searchers deploy “sign traps,” such as smoothing dirt patches to check for new footprints or reviewing footage from surveillance cameras. This framework was applied by Lankford to the cases of Sylvia, Fowler, and O’Sullivan to structure the search efforts. The book argues that failing to swiftly and accurately determine the IPP can lead to “a bastard search” (108), wasting critical time and resources, and potentially making the disappearance unsolvable.