The first tables shows the classification of Dutch penitentiaries and the type of treatment available in each separate penitentiary as of December 31, 1977. Statistics on personnel indicate that 4006 persons were employed in 1977, up from 3970 in 1976; 2251 worked as guards. The prison population was 26,955, up 6 percent from 25,677 in 1976. The average prison stay was 41 days. About 44 percent of the prisoners were in preventive detention, 49 percent in prison, and 1.8 percent in custody. About 19 percent of the inmates were under 21 years of age and 71 percent under 30. Of the 25-year-old men, 46 percent were in preventive detention and 51 percent in prison. Catholics outnumbered members of all other churches together by about 1.5 to 1. A total of 658,369 of the 775,677 work days expected of inmates were completed. The average daily wage was 3.50 guilders. Of the 977 prisoners eligible for parole, 760 were paroled and 195 still awaited parole decisions. In 1977, 16 persons were imprisoned for unpaid debts, 13 of them under bankruptcy laws. Supplementary tables show individuals placed under control of the government, the movement of the prison population within the corrections system, and population of the various prisons. A graph traces the trends in prison population from 1960 to 1977.