Operative research is the process of learning how things work in a particular area. As an investigator, I often have to learn how something works or the nature of the skills used in a certain area of human endeavour.
I sometimes start by interviewing people who are in the field, but more often, I do a literature search of the topic before conducting interviews. That leaves me with the task of locating relevant published material that will give me an overview of the topic and allow me to formulate a list of questions to ask during interviews.
The first task in this is to understand how the subject matter is indexed. That means understanding who might have a use for this material. For example, many military topics are also useful to engineers, construction companies, outdoorsmen, miners, sailors, and many more individuals and organisations. Another example would be the topic of physical security.
Once you know who might collect and catalog the subject material that interest you, learn what terms they might use to describe the material. Now add the words “library” and “subject guide” to your search. What you are looking for is a targeted collection of material. Once you find such a collection search the site using the site: operator.
Using the above search strategy in a recent search for information on evacuation of urban areas, I found urbansruvivalsite.com and its library of ebooks. While searching for data on electrical wiring led me to the Pole Shift Survival Information site and its library of publications about wire where I found tables of wire-gauge sizes. When trying to decipher old shorthand notes in a deceased lawyer’s file I found a library of publications about shorthand.
The focus of each of these ‘library’ sites is far removed from my interests, however, the people who created these sites had their own use for the information and that made my job easier.