Some social groups within Australian society are at higher risk of mental disorder than others. The relative size of these higher risk groups varies over time, affecting the overall rate of mental disorder in the population. Three social characteristics associated with mental disorder are age, employment/unemployment and type of family circumstances. The distribution of these social characteristics in the population has changed and these changes have sometimes had a disproportionate effect on males. These changes include: increasing rates of long-term unemployment; changes within the family requiring men to give up some of their power; changes in family life such that marriage is a more flexible institution, with increasing proportions of the population experiencing marital changes; and an increase in the rate at which children are separated from a parent.