Floor finishes can be stripped using a substantially nonchlorinated concentrate comprising a floor finish dissolver and an at least partially water-unactivated water thickener. The concentrate is diluted with water at an intended use location to activate the water thickener and noticeably increase within sixty minutes or less the viscosity of the resulting mixture, then applied to a hardened floor finish atop a floor and allowed to soften or dissolve the floor finish so that the finish may be removed from the floor.