In the long run, this holistic approach to dealing with pests should reduce pesticide use, provide economic savings for the farmer and protect both the environment and human health. The term ‘integrated’ implies incorporation of natural enemy/antagonist levels into decision-making, and use of compatible, non-disruptive tactics that preserve these agents. Integration can be viewed as either vertical (i.e., within a class of pests; sometimes called first-level) or horizontal (i.e., among all classes of pests; sometimes called second-level). For example, an insecticide applied for control of an insect pest that also kills natural enemies of that and other insect pests represents a lack of vertical integration; similarly, a fungicide applied for plant disease management that also kills natural enemies of insect or mite pests represents a lack of horizontal integration. Historically, the lack of such integration has been one of the major impediments to the implementation of IPM in agriculture.