Bi₂Sr₂CaCu₂O_x(Bi-2212) is the only high-temperature superconductor that can be made into isotropic round wires. Because of their excellent engineering critical current density and simple fabrication, Bi-2212 wires have been successfully applied in several kinds of high field magnets. The development of the powder in tube method, including precursor powder processing, deforming, and high pressure heat treatment, is briefly reviewed. The recent performance and applications of these wires are described, and the key issues in producing high-performance wires are discussed.