Private detectives and investigators need knowledge in the following areas:

• English Language: The meaning and use of the English language.
• Customer and Personal Service: Providing special services to customers based on their needs.
• Law, Government, and Jurisprudence: Laws, rules of the court, and the politics.
• Computers and Electronics: Computer hardware and software.
• Clerical: General office work such as filling and storing information.
• Administration and Management: How to run a business or group.
• Public Safety and Security: How to protect people and property.
• Psychology: People, their actions, and mental processes and how to treat problems.