The diverse substance abuse rehab programs which are offered to alcohol and drug addicted individuals in Knoxville can vary in many different ways. Some alcohol and drug abuse rehab services take place in a residential or inpatient location, where individuals remain for the duration of their rehab which provides a more therapeutic rehab setting. Others offer drug and alcohol abuse rehab services on an outpatient basis which provides a sense of flexibility, though outpatient facilities are not always an appropriate substance abuse rehabilitation program for individuals in Knoxville who are having difficulties with long term addiction problems. Regardless of whether inpatient or outpatient substance abuse rehab services are chosen, there are also different amounts of time that people will be expected to continue to be in the drug rehab facility. For example, many short-term programs provide services for 4 weeks or less, whereas long-term facilities will require at least a 90 day stay.