2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/40188I discuss effective field theories for heavy bound systems, particularly bound systems involving two heavy quarks. The emphasis is on the relevant concepts and on interesting physical applications and results.21 pages, latex, 8 figures; Invited talk given at the XXIII International Workshop on the Fundamental Problems of High Energy Physics, Protvino (Russia), June 2000. Few misprints correctedHigh Energy Physics - PhenomenologyHigh Energy Physics - LatticeHigh Energy Physics - Theorytext