1) Researchers developed 3D human liver tissues using parenchymal and non-parenchymal cell populations from an automated 3D bioprinting platform. 2) The resulting liver tissues exhibited organized structure, expression of key proteins, and ability to secrete liver proteins for 6 weeks. 3) The tissues also expressed phase I drug metabolizing enzymes over 28 days, including induction of CYP3A4 activity in response to rifampicin, demonstrating their potential utility for drug development and toxicity testing.