Saccharomyces cerevisiae 4094-B (a, ade-2, ura-1) in potassium phosphate buffer with glucose under aerobic conditions took up (-)S-adenosyl-L-methionine from the medium in sufficient quantity to permit the demonstration of its accumulation in the vacuole by ultraviolet micrography. The same result was obtained with (-)S-adenosyl-L-methionine, (i)S-adenosyl-D-methionine, and (-)S-adenosyl-L-ethionine. The rate of uptake was slow with (-)S-adenosyl-S(npropyl)-L-homocysteine and S-adenosyl-D-homocysteine. S-Adenosyl-Lhomocysteine was assimilated rapidly, but intracellular degradation precluded accumulation and ultraviolet micrographic studies. The uptake of 5'-methyl-, 5'-ethyl-, 5'-n-propylthioadenosine, and 5'-dimethylsulfonium adenosine was minimal.