In 1984 an Alternative Birth Clinic (ABC) was opened at the Copenhagen County Hospital in Glostrup. The ABC was opened on a trial basis to evaluate the demand for a different and more peaceful birth and nursing environment. The study was performed to illustrate how the place of birth can influence the delivery and the duration of breast-feeding. During the observation period of seven months there were 125 uncomplicated births at the ABC, and 170 uncomplicated births at the obstetrical ward. It was not possible to perform this study as a randomized one as delivering at the ABC was on offer to all women in this part of Copenhagen County. The newborn children at the ABC were nursed during the first 30 min after birth by 73.1% of the mothers compared to only 48.1% of the mothers at the obstetrical ward. On the fifth day after delivery 79.7% of the mothers at the ABC breast-fed without supplementary infant formula, while 95.1% of the mothers at the obstetrical ward breast-fed without supplement. Fourteen weeks after delivery 68.4% of the mothers who delivered at the ABC were breast-feeding without supplement, compared to 51.8% of the mothers who delivered at the obstetrical ward. The success of breast-feeding was found to have a positive correlation to higher social groups, delivering at the ABC, the number of antenatal care visits and increasing maternal age. The significance of these factors was tested in a regression analysis which revealed that birthplace and social group were the two factors that could explain the differences in the course of breast-feeding. Women referred to the obstetrical ward because there were no vacancies at the ABC (ABC-refused) followed in all aspects the mothers at the obstetrical ward. In spite of the groups not being randomized we feel that we can conclude, especially taking into consideration the results from the ABC-refused group, that the differences in the success of breast-feeding can be.