Insect proofing at the time of construction offers new challenge and opportunity to the building and pest control industries. It provides the opportunity for prevention, which is generally less expensive and always more satisfactory than cure. Some insects such as house flies and mosquitoes are not amenable to control by this method—their control is primarily a community or regional problem. Some other insects such as ants, sowbugs, fleas and clover mites, may gain entry into buildings through areas where they don't have to cross the inorganic powders applied during construction. Nevertheless, insect proofing during construction provides the means by which a high degree of long-term control of certain important structural and household pests can be effected.