While police departments usually handle crimes and missing persons cases, some families also opt to hire private investigators to assist in a particular case.
Charlie Parker, one of the city's best-known private investigators, says the process of solving a case can be complex and rigorous, but it is one that must be executed with attention to detail.
As he begins each individual case, Parker assesses the victim or individual and their environment in a method he calls "victimology."
"We want to learn about you (the missing person). That's called victimology," Parker said. "So when we leave here, we know about you, we even ask for video of you, if the family has it."
Parker looks at every aspect of a person's life, including social media habits, friends or neighbors one associates with, hobbies and interests, and work patterns.
He also conducts a thorough search of his or her home -- personal belongings, computers, and missing items in the home -- as he looks for clues.
"We would look at her pictures, we would look at her books, what kind of books did she read?" Parker said. "These people here, who are they, how do we locate them?"
Parker, who has worked several high-profile cases, including the disappearances of Joshua Davis, Pauline Diaz, and Leanne Bearden, says about half of all families who request his services are in search of a missing loved one.
"You dig and dig and try to find out everything about them," Parker said.
Though Parker's specialty is missing persons cases, he's had experience in other crimes, from rapes to kidnappings, that are far more sinister.
The key to solving them, Parker said, can be uncovered in the tiniest of details.