Apoptosis is a type of cell death that contributes to several devastating neurodegenerative disorders including Parkinson?s disease (PD) and amyotrophic lateral sclerosis (ALS). Consequently, identification of molecular pathways that regulate neuronal apoptosis is a key to developing novel therapies that slow or halt neurodegenerative diseases. Mitochondria are cell structures responsible for energy generation. In addition, they are the source of most of the oxidative stress cells experience. Importantly, mitochondria also control a specific form of cell death (apoptosis). In many neurodegenerative conditions, activation of a mitochondrial apoptotic cascade is a precursor to neuronal death. Mitochondrial apoptosis is regulated by the Bcl-2 protein family.