Social scientists have studied and debated the "causes" of crime for centuries, with theories ranging from poverty and inequality to greed and pure evil. Fortunately for corrections professionals, much criminal behavior can now be understood and changed even though these arguments still rage.

At a practical level, criminal acts occur when there is a motive, a means and an opportunity. There must be a ready offender, a vulnerable victim, and a lack of sufficient guardians to discourage the crime from happening. Successful supervision attempts to reduce all three factors. It especially focuses on increasing the supports to prevent criminal conduct.

It is critical for staff to understand the underpinnings of criminal behavior, that is, what makes a "ready offender." While the entire spectrum of human behavior cannot, of course, easily be summarized, research has consistently identified a set of characteristics that are common among criminal offenders and relate closely to recidivism. These characteristics, which both predict and influence criminal behavior, are often called "risk factors" or "criminogenic needs."

Some risk factors are static and cannot be changed. Static factors include having a family history of substance abuse or a prior record of delinquency. Other factors can be changed. These dynamic factors include having antisocial friends or poor verbal and problem-solving skills.

Dynamic needs are further distinguished between those that are "criminogenic"
and "non-criminogenic."