Since military service in Italy is obligatory for all 20-year olds (“conscripts”) who do not choose to perform alternative civilian service, we thought of utilizing the data derived from the examinations all conscripts undergo, and selecting information relative to twins. The material we have gathered from the country's Draft Boards concerns the period from October 1987 to December 1988, and this information allows to determine: 1) the twin status of a conscript and the identification of his cotwin; 2) aptitude for military service; 3) occupation; 4) presence of twins in the father's or mother's lineage; 5) home address and telephone number.

The twin material collected concerns 2,739 male pairs and 1,433 pairs of both sexes, classified with respect to:

1) Aptitude for military service;

2) Choice of occupation;

3) Presence of twins in the family.