Single-molecule magnets (SMMs) display slow relaxation of the magnetization, purely of molecular origin, in the absence of an applied magnetic field. This review summarizes the important role played by organometallic chemistry in the recent development of SMMs. The broad applicability of organometallic synthesis has led to a series of organometallic SMMs containing transition metals, lanthanides, or actinides, with several examples accounting for some of the most fascinating low-temperature magnetism. The review has two main aims. The first aim is to provide organometallic chemists with an introduction to one of the most exciting areas of modern molecular magnetism and, in particular, to highlight how organometallic chemistry has allowed the field to evolve in new directions. The second aim is more of a clarion call: organometallic chemistry still has hugely underexploited potential in the development of single-molecule magnets, and it is reasonable to expect that different synthetic approaches will lead to new and unusual magnetic phenomena. By using this review as an entry point for studying the literature in more detail, hopefully more organometallic chemists will consider directing their synthetic repertoire toward the design and realization of new, and possibly improved, single-molecule magnets.