The coactivator PGC-1alpha is a key regulator of mitochondrial biogenesis and respiration, mediating expression of several transcription factors required for these programs. Three new studies reveal that PGC-1alpha expression is downregulated in patients with Huntington's disease (HD) and in several animal models of this neurodegenerative disorder, implicating PGC-1alpha in HD pathogenesis and providing a connection between impaired energy metabolism and neurodegeneration.