There is a growing interest in geriatric practice directed at elderly people living at home. There are, however, few studies on the economic aspects of this type of care. This article deals with a cost-effectiveness analysis of the Dutch Geriatric Intervention Program (DGIP) from the standpoint of the health system, compared with that of usual management, after six months follow-up in elderly vulnerable subjects. This cost analysis was carried out during the course of a randomised, controlled, single-blind study (DutchEASYcareStudy: ClinicalTrials.gov Identifier NCT00105378). The difference in treatment effect was calculated as the difference in proportions of patients who were treated successfully (prevention of functional deterioration and improvement in quality of life). Additional treatment costs were calculated as being the excess over mean total cost of care. The Incremental Cost-Effectiveness Ratio (ICER) was expressed as total cost per successful treatment. Bootstrap analysis was used to determine the confidence intervals of these values.