Balance,of l~laifitC11ance and adaptive activities. Open sys tems seek to reconcile two, often conflicting, activities. Mainte nance activities ensure that the various subsystems are in balance and that total system is in accord with its environment. This, in effect, prevents rapid changes that may unbalance the system. In contrast, adaptive activities are necessary so that the system can adjust over time to variations in internal and external de mands. So whereas one seeks stability and preservation of the status quo through the purchase, maintenance, and overhaul of machinery; recruitment and training of employees; and mech anisms such as the provision and enforcement of rules and pro cedures, the other focuses on change through planning, market research, new-product development, and the like.