The LIPID MAPS Spring School, held in Cardiff City Centre from 12th - 16th April 2021 focussed on theoretical and practical aspects of lipidomics using state-of-the-art approaches. With a major focus on the underlying biology and biochemistry of lipids, including their roles in health and disease. The event will featured more than 20 sessions over five days, covering an introduction to MS-based lipidomics and all aspects from sample preparation, storage, chromatography, instrumentation, and identification using databases including LIPID MAPS. A dedicated session on novel technologies, such as iKnife, REIMS, imaging, and new standards for quantitation. With practical tutorials on software and informatics tools for lipidomics. The event will also included an introduction into data integration using biostatistics and systems biology, to include lipid biology/ biochemistry, MS-based lipidomics and quantification using targeted methods.