The aim of this study was to analyse how long babies born in Akureyri district in 1990 were breast-fed, compared with babies born in 1985. Possible predictive factors for the length of breast-feeding were studied by univariate and multivariate analyses. From 1985 to 1990, the proportion of infants exclusively breast-fed at the age of 3 months increased from 57% to 70% (p < 0.01) and for those breast-fed exclusively or partially, from 67% to 83% (p < 0.01). By 1990, 64% of all babies were breast-fed at the age of 6 months, compared with 43% in 1985 (p < 0.01). The factor with the strongest correlation with a long breast-feeding period was a well educated father. Other factors correlated with the duration of breast-feeding were the mother's age, number of previous children, attending a maternity course, and being a non-smoker. It is concluded that real beneficial changes regarding the duration of breast-feeding in Iceland have been observed during the last decade, but the objectives of the preventive measures recommended by health authorities have not yet been reached.