β-Glucocerebrosidase (GCase) mutations lead to glucosylceramide build-up in the lysosome, impacting α-synuclein aggregation and autophagy. Recently, Baden and colleagues found GCase in mitochondria, supporting mitochondrial complex I function and energy metabolism. We believe the newly described role of GCase in the mitochondria will inform new Parkinson’s and Gaucher’s disease therapeutics.