The 22nd International Biohydrometallurgy Symposium (24 - 27 September, 2017, Freiberg, Germany) was the global forum for experts from academia and industry active in the fields of biomining, bioleaching and bioremediation. These technologies have a high potential to establish environmentally favourable processes for the recovery of primary and secondary precious and base metal resources as well as the remediation of exploited mining sites.