Phosphatidylserine (PS), a ubiquitous, endogenouslyoccurring phospholipid, is the major acidic phospholipid in the brain. PS is embedded in cell membranes, and along with other phospholipids, makes up the basic structural components of the cell membrane. These membrane phospholipids play an important role in cell-to-cell communication and transfer of biochemical messages into the cell, which trigger cellular responses. The proper functioning of these processes is of ultimate importance, especially in the central nervous system. It is theorized that PS enhances cellular metabolism and communication by influencing the fluidity of cell membranes. 1-4 Oral supplementation of PS has been shown to affect neuronal membranes, cell metabolism, and specific neurotransmitter systems, including acetylcholine, norepinephrine, serotonin, and dopamine.1-4 Numerous clinical trials have established that PS exerts significant benefit for cognitive functioning, especially those functions which tend to decline with age, including memory, learning, vocabulary skills, and concentration.