As the most abundant excitatory neurotransmitter in the brain, glutamate plays an important role in numerous aspects of normal and pathological brain function. This book provides an overview of the role of metabotropic glutamate receptors (mGluRs) in basic brain functioning, such as autonomic regulation, synaptic plasticity, and learning and memory. Also provided are up-to-date summaries of recent progress towards identifying how mGluRs both mediate and represent novel pharmacotherapeutic targets for the treatment of various neurological and neuropsychiatric disorders, such as depression, anxiety, schizophrenia, amyloidogenic disorders and substance abuse.