Poor health is not a nine-to-five condition. People can "catch a bug" or suffer flare-ups of ongoing illnesses at any hour of the day or night. Knowing this, the best primary health care practices offer their patients after-hours care. And when they do, patients benefit from having providers who know them and who can deal with their problems quickly and effectively. The health system also benefits, because patients don't get duplicate tests and treatments (for conditions already known) or use expensive hospital emergency rooms.