Handbook on the Physics and Chemistry of Rare Earths: Including Actinides, Volume 67 highlights new advances in the field, with this new volume presenting interesting chapters written by an international board of authors. Updates in this new release include Emerging trends in the design and potential applications of luminescent lanthanide coordination complexes for photodynamic therapy, Deciphering crystal field splitting of lanthanide ions using magnetism, luminescence and ab initio calculations: a friendly discussion between van Vleck and Boltzmann, The Heavy Rare Earths' Supply Chain, and more.