Mitochondria, the energy producers of the cell are also the hub of an array of cellular processes such as calcium signaling, apoptosis, heme biosynthesis, cholesterol metabolism, hormone synthesis and ROS production. Since mitochondria are involved in a myriad of cellular functions, they are at the centre-stage of diverse human pathologies including many degenerative diseases. Topics discussed in this compilation include therapeutic targets in ischemia reperfusion injury and cancer; an energetic approach to insights on mitochondrial roles in cardiac stunning and cardioprotection; and mitochondrial dysfunction of a coworker in treatment of trypanosoma cruzi and leishmania amazonensis infection.