As the steel industry expands worldwide, slag dumps with transition metals (especially chromium and vanadium) are becoming more common, posing a serious environmental threat. Understanding the properties of slags containing transition metal oxides, as well as how to use the slags to recover and recycle metal values, is critical. Toward this end, the University of Science and Technology Beijing (USTB) and Royal Institute of Technology (KTH) have been collaborating on slags containing transition metals for decades. The research was carried out from a fundamental viewpoint to get a better understanding of the structure of these slags and their properties, as well as industrial practices. The research focused on the three “R”s, viz. retention, recovery, and recycling. The present paper attempts to highlight some of the important achievements in these joint studies.