2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42799This note reviews the latest measurements of $α_s$ from event shapes in $e^+e^-$ annihilation at LEP1 and LEP2. A critical review of different methods to extract \as is offered.to be published in the proceedings of the DIS03 workshop, St. Petersburg 23.-27.april, 2003 (references added)High Energy Physics - Phenomenologytext