The Architectural Detective Agency (ADA) was founded in 1974 by architect-historians Terunobu Fujimori and Takeyoshi Hori while they were graduate students. They undertook field research to document structures that were disappearing or that had been excluded from official Japanese architectural history. The detectives walked with cameras and sketchbooks, taking stock of the city. They dressed for infiltration as well as documentation.
When buildings were threatened with demolition, the detectives mobilized to produce complete sets of photographic and drawn documentation, often interviewing architects and collecting as much reference and archival material as possible.
Here is an account of the ADA published in Space Modulator 47 (May 1976) describing ADA’s history and methodology, explaining how to enter private properties, what to wear, how to photograph, how to research, and giving other tips.