Endocannabinoids are a family of lipid messengers present in a wide range of living organisms. They bind and activate the membrane receptors that are targeted by Delta(9)-tetrahydrocannabinol, the main psychoactive principle in marijuana (Cannabis). In the brain, they regulate ion-channel activity and neurotransmitter release critical to biological processes such as synaptic plasticity and learning and memory. Endocannabinoids are embedded within an intricate network of lipid pathways, the regulation of which controls the strength and duration of their signaling. Therefore, physiological, pathological, or pharmacological perturbations of these interconnected lipid pathways have a profound effect on the regulation of endocannabinoid signaling. The recent development of high-sensitivity and high-throughput analytical tools affords a broader view of the endocannabinoid system, allowing researchers to place individual endocannabinoid molecules in the context of the interconnected network of their precursors and derivatives. Targeted lipidomics provides new opportunities for understanding endocannabinoid metabolism.