Section 1: Molecular Biology, Biochemistry, and Functioning of the GABAB Receptor.- GABAB Receptor: Molecular Organization, Function, and Alternative Drug Development by Targeting Protein-Protein Interactions.- GABAB Receptor Functioning: Focus on Allosteric Modulation.- Section 2: Pharmacology of Baclofen.- Historical Overview on Baclofen, the Only GABAB Receptor Agonist Approved and Available for Clinical Use.- Baclofen for the Treatment of Spasticity and Dystonia in Cerebral Palsy.- Baclofen for the Treatment of Cough.- Baclofen for the Treatment of Alcohol Use Disorder.- Baclofen Safety, Toxicity, Withdrawal, and Overdose.- Section 3: Chemistry and Pharmacology of Positive Allosteric Modulators.- Recent Advances on Chemistry of GABAB Receptor Allosteric Modulators.- GABAB Receptor Positive Allosteric Modulators: Novel Approaches for Drug Design and Discovery.- Recent Advances on GABAB Receptor Positive Allosteric Modulators as Potential Pharmacotherapies for Neuropsychiatric Disorders.- Recent Advances on GABAB Receptor Positive Allosteric Modulators as Potential Pharmacotherapies for Substance Use Disorder and Food Addiction.- Recent Advances on GABAB Receptor Positive Allosteric Modulators as Potential Pharmacotherapies for Alcohol Use Disorder.- Section 4: Miscellanea.- ?-Hydroxybutiric Acid: A GABAB/GHB Receptor Agonist with a Unique Neuropharmacological and Therapeutic Profile.- Naturally Occurring GABAB Receptor Ligands.- Norman G. Bowery: A Founding Father of the GABAB Receptor Research Field - Reflections on His Contribution.