Two methods of autologous splenic implantation, with sliced or with minced splenic tissue, were compared in six pigs. The two procedures were carried out simultaneously in each pig and the splenic remnants were surgically removed three months later. These remnants were histomorphometrically quantified by point counting. Statistical analysis showed the mincing procedure to be significantly superior, since 33% of the originally implanted tissue remained, in contrast to 21% of sliced, implanted tissue. At microscopy the tissue remaining after both procedures was in all cases indistinguishable from normal pig spleen. No necrotic splenic tissue was found. The authors conclude that minced tissue and omental pouch technique are preferable for autologous splenic implantation.