Here's a brief description of what each Ingredient can do. 

Glycine - helps you fall asleep quicker, reduces symptoms of insomnia, improves overall quality of sleep, increases length of time in R.E.M. sleep. Glycine causes an increase in serotonin which is used to synthesise melatonin. It also causes an increase in blood flow to the extremities through vasodilation which lowers the core body temperature which is important for the onset of sleep. 

Magnesium Bisglycinate- Magnesium plays a role in over 300 different enzyme reactions in the body to help with nerve and muscle function, blood pressure,  and the immune system. It helps regulate Gaba (an inhibitory neurotransmitter that promotes calmness). Magnesium can help reduce anxiety by balancing the parasympathetic and sympathetic nervous systems. 

L- Theanine- can positively impact key neurotransmitters involved in stress, sleep, mood, focus and memory. It enhances production of dopamine and serotonin and appears to play a role in the formation of Gaba. Theanine promotes balance in the neurotransmitter system. Taking theanine will help you fall asleep quicker and have less disturbances. It also promotes relaxation through increased alpha-wave activity in the brain. 

Valerian root - helps you relax and can help decrease anxiety. Can help increase the amount of Gaba available in the cns. Reduces time to fall asleep and helps with sleep quality. 

Chamomile extract - contains apigenin that promotes sleepiness. Has a calming effect.