Regular prayerful examination of one's conscience by concentrating on some one particular moral failing to be overcome or virtue to be exercised. Its focus is on such external manifestations of the fault or virtue as can be remembered for periodic inventory. Particular examens are changed weekly, monthly, or otherwise in order to ensure maximum attention. They are also commonly associated with some brief invocation for divine assistance, as occasions arise for avoiding a sin or acting on a virtue. And after some time another cycle may be started of the same defects that this person has to conquer or good habits he or she needs to develop.