A concentrated non-aqueous cleaning solution having a long shelf life includes an ester and an anhydrous surfactant. The ester is the active ingredient for dissolving graffiti, grease and other contaminants. The ester can be one of or a mixture of dimethyl glutarate, dimethyl succinate, dimethyl adipate, ethyl lactate, and a methyl ester extracted from soybean oil. The anhydrous surfactant is preferably alcohol ethoxylate. The ester in the concentrated solution does not degrade into an acid and alcohol as long as the solution is not mixed with water. This allows the concentrated solution to be shipped and stored and remain efficacious. The concentrate can be diluted with water immediately prior to use. Diluting before use makes the graffiti cleaner less expensive and prevents damage to sensitive surfaces but does not provide long enough time for the ester to degrade.