The composition dependence of the room-temperature average atomic volume is analysed for early and late transition metal (TE–TL type) and metal–metalloid (TL–MD type) amorphous alloys. For the Zr–Cu, Ti–Cu and Hf–Ni sytems, the data suggest an ideal solid solution behaviour. For the other TE–TL systems, two composition ranges can be distinguished (20–70 at.% TL and 84–93 at.% TL). For each composition range, a specific atomic volume V a-Zr can be assigned to the Zr atoms that has the same value for any of the alloying components TL = Fe, Co and Ni. For TE-rich compositions (range 1), V a1-Zr ≈ V hcp-Zr whereas for TL-rich compositions (range 2), V a2-Zr < V a1-Zr. For the TL atoms, whereas both V a2-TL(TE–TL) and V a-TL(TL–MD) are fairly close to the V TL values of the close-packed crystalline structures, the V a2-TL(TE–TL) values are smaller by as much as about 2–3% than the V a-TL(TL–MD) values.