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Homeostatic and adaptive control mechanisms are essential for keeping organisms structurally and functionally stable. Integral control is a control engineering concept,��which has long been known to keep a variable A robustly at a given set-point by feeding the integrated error back into the process where A is generated.��However, how robust homeostasis and integral control is realized in biochemical systems is still not fully understood. We have recently identified two reaction kinetic��conditions that permit to build integral control into chemical negative feedback structures and which allow to generate biochemical models of robust��homeostatic controllers. In their simplest form such��”homeostats”��consist of two compounds: the homeostatic controlled variable A and a controller molecule E, where��the concentration of E is related to the integrated error between the concentration of A and its set-point. We show how combinations of basic controller motifs lead to homeostasis where uptake, storage, assimilation/transport and��remobilization��of a controlled compound are combined in an integrated manner. We further show how oscillatory��homeostats��can maintain stability in A by keeping the average concentration of A at��the controller’s set-point due to a change in the oscillator’s frequency. Because in oscillatory��homeostats��the average level of the manipulated variable E is associated with the frequency of the��compensatory flux, we show how robust frequency control may be achieved by controlling the average level of E. The occurrence of such��behaviors��in oscillatory signaling and in��biological clock rhythms is discussed.