The endocannabinoid system (ECS) was discovered when CB1 and CB2 receptors were found, the first of them in the central nervous system of pigs, and the second one in the periphery nervous system. The endocannabinoid system is involved in multiple physiological functions. These situations indicate that the ECS is a promising tool for the development of future drugs to treat several diseases including cancer and multiple sclerosis. In the first chapter, the chronobiology of ECS is discussed. The authors of the second chapter focus on anadamide, a type of endocanninoid, as a fast retrograde signaling molecule in neural circuits. In Chapter 3, the authors summarise their experimental data on neuroprotective effects of amide neurolipids and their structural analogues. In the final chapter, recent advances in terms of assay validation, instrument configurations and matrix interference for anandamide determination in biological matrices are explored.