So you can see that the use of a guard column has a lot to do with personal preference. My preference is not to use guard columns – I think the hassle-factor isn’t worth the potential financial savings. In any event, you should make a careful evaluation of the financial and chromatographic benefits and risks before you use a guard column. Does it improve the quality of your data? Does it improve the reliability of the HPLC system? Does it extend the lifetime of the analytical column? These and other questions will help you to decide if a guard column makes sense for your method.