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Soft materials capable of transforming between three-dimensional (3D) shapes in response to stimuli such as light, heat, solvent, electric and magnetic fields have applications in diverse areas such as flexible electronics^,, soft robotics^, and biomedicine^{, –}. In particular, magnetic fields offer a safe and effective manipulation method for biomedical applications, which typically require remote actuation in enclosed and confined spaces^{, –}. With advances in magnetic field control, magnetically responsive soft materials have also evolved from embedding discrete magnets or incorporating magnetic particles into soft compounds to generating nonuniform magnetization profiles in polymeric sheets^,. Here we report 3D printing of programmed ferromagnetic domains in soft materials that enable fast transformations between complex 3D shapes via magnetic actuation. Our approach is based on direct ink writing of an elastomer …