The software for analysis of the Health Habits and History Questionnaire (HHHQ) has been revised and is available to researchers. As in earlier versions of the software, questionnaires other than the standard National Cancer Institute versions can be analyzed. Foods can be added or dropped, nutrients can be added or changed, and many other revisions and options are facilitated. Estimates of 33 nutrients and up to 20 user-defined food groups are produced. The validity is unchanged from the previous software. Other features include a data entry key-and-verify system, standardized editing, a computer-assisted interview, and the calculation of health indices including pack-years of smoking and social network index.