Drug tests are legal in many countries.  For many employers, it is desirable that employees are drug free.  Employers may have policies about drugs on company property and the use of drugs while working to support their desired drug free atmosphere. 

Depending on where you live, the drug test laws may vary and it is important that you research the drug test laws that apply to you.  In some legal cases, drug tests can be mandatory according to any conditions that apply.  In the case of an employer, there are certain conditions that must be met in order to use drug tests.   

A company may drug test potential employees or test an employee after an event, which causes suspicion that the person may be a drug user.  Usually, random testing is done in situations where safety is a concern.  For workplaces where considerations such as safety, security, operating machinery or driving a vehicle are important to the job, it is highly desirable and standard that all employees be drug free while performing their duties.  The military is another sector where drug tests are administered.  As an employee, you must consent to the drug test before it is carried out.   

It could be considered that drug tests may be an invasion of a person's body and privacy particularly if the employer is forcing an employee to undergo a drug test.  Depending on the type of drug test, there will be different levels of invasiveness.The most invasive drug test is the blood test while the least invasive is the hair or urine drug test.     

When undergoing a drug test, a person may feel as if their private life is being examined at too much depth.  Before you refuse a drug test, you should find out whether such a refusal as submitting to a drug test will result in disciplinary action such as dismissal or some other consequence.   

Depending on the situation, you could lose your freedom or your job, so consider all aspects of a drug test before you make your decision about what you will do if you have to do anything.  The best thing that you can do to pass a drug test is to become informed as much as you can so that when a drug test is in your future, you will be able to deal with the situation as best as you can.   

Since it is possible to pass some drug tests through different strategies, you could find a positive outcome to your drug test even if you have used recreational drugs such as marijuana in the recent past.  The more information that you have, the better your chances are of passing the drug test.