Criminal Investigators are responsible for solving crimes, preventing future criminal activities, and identifying and detaining suspects. They may specialize in analyzing evidence, performing surveillance, or conducting searches and interviews. Those who specialize in surveillance use special equipment to find out more about suspicious organizations or persons. Professionals working on crime scene investigation are required to examine scenes and collect different types of evidence such as clothing samples, fingerprints, and weapons.

Criminal Investigators usually perform many of the following tasks:
• Interrogating suspects.
• Preparing reports.
• Gathering evidence.
•   Searching through computer files to prove guilty of suspected criminal.
• Directing the investigation process.

• Having interpersonal skills.
• Being observant.
• Having good communication skills.
• Being able to use various equipments such as photocopy machines and cameras.
• Having public speaking skills.
• Being able to interpret and apply new information to a situation.
• Having time management skills.
• Being physically fit.
• Having logical thinking.
• Being self-motivated.

Applicants for Criminal Investigator jobs need to have a Degree in Criminal Justice or Police Science. They are also required to have courses in psychology, English, advanced science, and computer. Candidates who want to work at forensic crime labs need to have a major in biological sciences to learn about applications of scientific research and laboratory testing techniques. Applicants for jobs at federal level usually have a Master´s Degree related to this field in order to obtain better job opportunities and improve their credentials. Employers in this field usually seek persons having suitable experience as hotel investigators, security guards, loss prevention managers, and police officers.