A basic attentive maintenance model has three lists of different sequences of observations leading to actions. Each observation (arrow) can lead to a different action (box), or multiple observations may lead to the same box. Each action in an attentive maintenance model is a decision made about which, if any, instances of an ecological resource will be used or obtained in a particular way. The same ecological resource is under consideration in each box of a single attentive maintenance model. Observation-action pairs are placed into the three lists according to how frequently the observations recur.