My aim is to clear any stress and/or confusion that is most likely present for anyone who has been asked to complete a drug screening for the pre-employment process. Personally I don't think giving out your stats and smoking frequency helps too much but nonetheless: I am 5'9", 160 lbs, 20 y/o, and am a semi-frequent smoker (2-3 times a week). For part of my pre-employment process I was notified on a Wednesday that I had to take a drug test with LabCorp by the following Monday at 4PM. Naturally I flipped out since the last time I had smoked was Saturday, leaving there only 9 days from the last sesh until my test. I started researching the shit out of it learning about detoxing the day of, dilution, substitution, etc and drinking water and cranberry juice like none other. I bought a detox drink but returned the next day after hearing a ton of mixed reviews and feeling unsure about it. I then bought a digital candy thermometer (local pharmacy), 3 oz. traveler's shampoo bottle(local pharmacy), and hand warmers (local sporting goods store) just in case I decided to go for substitution. My next purchase was two at-home THC drug tests from Walgreens. I took one on Friday afternoon and passed it to my surprise. So I kept drinking water and cran juice and took my second test on Sunday morning (day before test) with my first pee of the day and passed again with a clear second line. I was still paranoid and was unsure about the accuracy of the home tests so I looked in to that as well. Drug tests cost the employer money, and the more detailed the test is, the more expensive it is. Employers do not want to spend money on these higher tech tests if they don't have to. So before starting a job that drug tests you will have to take a immunoassay test, which uses antibodies to detect the presence of drugs and other substances in urine. The initial screening process does not measure the specific amount of drug present in urine samples. It provides either a positive or negative result, indicating the presence or absence of detectable drug. The more expensive type of test is the GC/MS. GC/MS is the abbreviation for gas chromatography/mass spectrometry, the testing methodology lots of labs use to confirm presumptive positive drug screen specimens. GC/MS provides identification of the molecule(s) based on characteristic fragmentation patterns at specific retention times. GC/MS is a tandem technology, utilizing a gas chromatograph coupled to a mass spectrometer. Basically immunoassay = cheaper and less accurate (cutoff level of 50 ng/mL) GC/MS = more expensive and more accurate (cutoff level of 15 ng/mL) The at home drug tests I bought had a cutoff level of 50 ng/mL as well so this made me feel a little better. As for my actual adventure at LabCorp this morning...it went something like this: I walked in the door and was greeted by this homie wearin a fresh pair of Js, good sign first of all. I had to provide ID, my registration number and sign in. There was no wait so I followed him to another room that had a sink and a bunch of other medical equipment in it. The process afterwards was interesting. It was reminiscent of a magician doing a trick, he told me to take off my coat and backpack, wash my hands, grab any sample cup from the drawer, inspect it for cracks, take of the plastic seal and empty the contents on the counter. After this he used a sharpie to mark how high I should fill it, showed me the temperature strip on the side of the cup and said that he'd have to check that within four minutes of me filling it (it had to be between 90-100 degrees F), and to not flush the toilet. The actual bathroom that he showed me to fill the cup in was just a 8x8 ft room inside of this bigger room and he said I could close the door. He was outside just around the corner the whole time but once I was inside I felt like I had a lot of privacy (could have EASILY done substitution if I wanted to). The toilet's water was also tinted blue so that they could prevent people from using the toilet water as part of a dilution technique and/or cooling process. I used the middle part of my stream just in case and filled it above his line. Once I came out of the room he made it clear that he poured it straight into the vile that would be sent to the lab and wrapped it tight inside the plastic bag. I had to sign and initial a few pieces of paper and that was it, so I bounced right after. I am still waiting on the results and will post when I hear but I hope this answers some people's questions. As a brief guide if you are worried about passing a drug test: 1) Do your best to find out if you will be supervised during the test (I was able to find it online) 2) Take an at home drug test. Just do it, it can't hurt and at least you'll know for sure before you start spending money trying to pass the real thing. 3) Decide on your plan of attack. Although I haven't tried all of the techniques, I would rank the reliability as follows: a. Substitution (if you have access to clean urine and will not be supervised, use the supplies I bought and PRACTICE GETTING THAT TEMP RIGHT). Don't even mess around with detox drinks, pills etc. if you can get clean urine! b. Dilution. There is a very good guide in these forums about dilution that seems to have a pretty high success rate, use this method if you have to. c. Masking. I personally don't recommend it, if an employer is even going through the trouble of testing you for drugs then they are going to be testing for masking agents as well, not worth it. 4) RELAX. Stick to your plan and execute it like your James Bond, no need to trip. If you've found yourself here then you are obviously an intelligent person who is capable of avoiding such a silly screening process. Good luck to all!