I have been using HDS services since 2002. Mostly it was the drug, then alcohol testing consortium. They have always been knowledgeable about the testing and making sure it was done correctly and my paperwork in the office was correct. More recently, with all the changes in DOT paperwork, and the larger driver files I have to have, HDS has always been able to answer my questions to make sure my driver files are correct. I would recommend Ivan and Marie to anyone needing this type of service.