Methods for applying a liner-free, or liner-less label, to a substrate, particularly glass or plastic (e.g., polyethylene terephthalate) substrates, are described herein. The method includes applying an adhesive composition, such as a polymeric coating, to a label face sheet, activating the adhesive composition with an activating fluid, and contacting the label to the substrate. The activating fluid is preferably a mixture of water and one or more organic solvents, such as low molecular weight alcohols.