If you work for the government as I do, the Supreme Court has ruled it's unconstitutional for you to be drug tested unless they are given a good reason. There are some limited exceptions but that's the basic idea. So, as long as you don't get high before work, don't get high during work, and don't tell anyone about your debauchery, you can go decades without fearing a single random drug test. In fact, my boss was a hippie in the 1960's, used to smoke tons of pot, and told me straight up that he doesn't care what I do in private, so long as I don't let it control my life. Werd.