The poor reviews on this product are based on lack of knowledge and understanding of the chemical and molecular properties of tandem. Tandem is demand CS with an added insecticide. THERE IS NO "CURE-ALL" SPRAY! Spray means nothing. Application and procedure is what matters most. The "smell" is very, very minimal. Like a weak paint thinner. The smell is the detergent in the chemical known as an emulsifier. That allows the oils of the product to bind with water. Before applying ANY chemical to ANYTHING regarding bed bugs, you MUST at LEAST consult information provided by universities such as Perdue, Kentucky, and the like . You MUST also be patient, for the insect has 5 cycles in life. Tandem is an excellent product. Top grade. Pest control has become indescribably better thanks to syngenta, Zoecon, and Bayer. I'd throw BASF in there, but they didn't produce termidor. They bought it from bayer