An artificial SI-Joint includes a sacrum component and an ilium component. The sacrum component may include a ridge, foundation, perimeter surface and a fitting member. The ilium component may include a polybearing, edge, foundation, perimeter surface, and a ridge or sockets. The fitting member of the sacrum component may engage the polybearing of the ilium component to restore normal movement of the SI-Joint. The artificial SI-Joint may be implanted as a single unit or as separate pieces that are coupled together.