The work of private detectives include cases of several types. The cases handled by them could be cases of:

DOMESTIC PROBLEMS

Requires the detective to investigate into the misdemeanours of the spouse, divorce, child custody etc.

FAMILY DISPUTES

These usually include cases of dispute over property or a will. 

INDUSTRIAL ESPIONAGE

These would include cases of theft and frauds, involving executives robbing industrial secrets patents, technical know-how and so on. Some companies require the credentials of potential employees to be checked. 

Some private detectives primarily concern themselves with the training and supply of security guards and bodyguards for organizations, industrialists and hotels.

Nature of work

The job of a private detective involves the use of various sophisticated techniques. These include trailing, interviewing, fingerprinting, photographing or even videotaping the movements of a person. 

The actual work or task of a detective begins after the client brings his case to discuss with the detective. Subsequently, a case is registered (akin to an FIR by the police) and all details are recorded in a confidential file. 

Next, a blueprint for the mode of investigation is prepared by the detective and the various tasks required in the case are delegated to a team of investigators who then implement the plan and do the follow up. 

Each investigator handles only a part of the entire case and none of them have knowledge of the case as a whole. Specialist knowledge of forensics and other such fields is needed. However most detectives use the services of a specialist in the field and hence do not have detailed knowledge of the same.