Leigh syndrome is a rare and severe mitochondrial disorder characterised by progressive neurological decline and symmetrical brain lesions. These sources explain that the condition arises from over 100 different genetic mutationsaffecting how cells produce energy, primarily through the depletion of ATP and increased oxidative stress. While no universal cure exists, patients are often managed with a "mitochondrial cocktail" of vitamins and cofactors to support metabolic function. Recent clinical developments include the accelerated approval of elamipretide for Barth syndrome and ongoing trials for promising new therapies like TTI-0102 and vatiquinone. Research is also advancing into gene therapies and mitochondrial transplantation to address the underlying genetic causes. Global patient registries now play a vital role in tracking the disease's natural history and accelerating the delivery of these targeted treatments.