Investigation or Investigations may refer to:

In law enforcement:

  • The work of a Private investigator
  • The work of a Detective
  • Federal Bureau of Investigation, the primary investigative arm of the US Department of Justice
  • Criminal Investigation Department, the branch of British Police force to which plain clothes detectives belong
  • Griffin Investigations, the most prominent group of private investigators specializing in the gambling industry

In medicine:

  • Clinical trial, an investigation conducted to collect data for new drugs or devices
  • Investigational New Drug, category in a USFDA program
  • Tests and scans done to help with the diagnosis or management of a disease

In other uses:

  • Forensic science, in fields such as accounting, science, engineering and information technology
  • Investigation (film), a 2006 Bulgarian drama
  • The Investigation, 1959 book by StanisÅ‚aw Lem
  • The Investigation (play), 1965 play by Peter Weiss
  • Investigation Discovery, a digital cable channel
  • Investigative journalism, the practice of in-depth reporting or analysis
  • "Investigations" (Star Trek: Voyager), the 36th episode of the television series Star Trek: Voyager
  • Investigations in Numbers, Data, and Space, a K-5 mathematics curriculum
  • Temporal Investigations, agency of the government of the United Federation of Planets in the fictional universe of Star Trek

Investigation may also be:

  • Discovery (observation)
  • Research