About Different Drawer Slide Mountings for Kitchen Cabinets
Undermount 
With under mount drawers, the drawer slide is attached to the bottom of the drawer as opposed to the side. There are a few advantages to having undermount drawers.
With undermounts, you actually gain more interior space due to not having to compensate for the space of the slides on the side - the gain is minimal, but you do gain some space. They are also slightly stronger than side mounts due to the weight being contained underneath. The sides of the drawer will remain bare because the metal slides will not be exposed. With undermount drawers, the option to have self-closing drawers is also available. To find out more, see our page on self close drawers.
Side Mount 
Side mounting is a common option for kitchen drawers and is a good option when built with high quality drawer boxes and high quality slide material.