This is the fourth in a Series of five manuals produced by the Social Security Department of the ILO to provide the reader with information on all the major elements of social security, including the principles, administration, financing, pension schemes and social health insurance. This manual takes a look at and makes comparisons between public and private pensions, methods of protection in public schemes, old age benefits, invalidity benefits, survivor's benefits. Of particular interest to certain countries will be a section dealing with transforming existing "provident fund schemes" into ones based on social insurance. Other manuals in this series: - Social security principles (Vol. I) - Administration of social security (Vol. II) - Social security financing (Vol. III) - Social health insurance (Vol. V)