A study of bone marrow cell content was carried out in 23 non-cirrhotic alcoholics, 20 cirrhotic alcoholics and 19 cirrhotic non-alcoholics compared with a control group of 12 healthy subjects, by means of sternal aspiration and bone marrow biopsy with histomorphometric quantification of fat in the latter. Although in the three pathological groups the mean values of fat area were superior to those of the control group, the only statistical differences found were between non-alcoholic cirrhotic and control subjects. The differences disappeared under covariance analysis with age as the correcting factor, showing a correlation between age and bone marrow fat content. To conclude from the biopsy the bone marrow of the cirrhotic is not hypercellular, contrary to the so far accepted findings obtained through sternal aspiration. Moreover, between the subjective global cellularity evaluation by biopsy and aspiration there was an important disagreement in 23.8% and an absolute agreement only 28.6% of cases. The non-existence of a linear correlation between fat content in bone marrow and liver, suggests that the two phenomena do not develop simultaneously.