Employers have adopted three major testing methods in the workplace, including urine, hair, and oral fluids. Each has unique attributes that make it the correct method under certain circumstances. Lab-based urine drug testing can be used to determine drug use for the prior three to four days, but the collection process presents challenges, such as the need to observe the collection process. In addition, urine testing is subject to various cheating methods. Hair testing provides a window of detection up to 90 days, but drugs are not detectable for about seven days post-use. Hair collections can take place anywhere but is typically more expensive than other testing methodologies. Finally, oral fluid testing is the best way to determine recent use, can take place anywhere, and is ideal for pre-employment testing in states where marijuana is legal.