The Spanish harpsichordist and conductor, Alfonso Sebastián Alegre, studied piano (Mª Pilar Armijo) and harpsichord (José Luis González Uriol) at the Conservatorio Superior de Música de Zaragoza (Class of 1992). He continues his training in at the Conservatoire National de Musique et de Danse de Paris, where he specialized in fortepiano (Patrick Cohën-Akenine) and studies of orchestral conducting (Claire Levacher) (Class of 1999). He has attended perfecting courses with Jan Willem Jansen, Gustav Leonhardt, Lars Ulrik Mortensen, Jacques Ogg and Paul Badura-Skoda, among others. He is a laureate in the modality of harpsichord and organ at the Concurso de Juventudes Musicales de España the Musical (Youth Competition of from Spain).

A member of the group Los Músicos de Su Alteza, Alfonso Sebastián has also collaborated with the ensembles La Tempestad, Al Ayre Español, Orquesta Barroca de Sevilla, Orquesta Barroca de la Universidad de Salamanca, Ensemble Vigo430, Orquesta Sinfónica de Castilla y León. As a soloist or in various formations, he has performed at important festivals and venues Ambronay, Utrecht, Friborg, Vieux-Lyon, Sorèze, Konzerthaus in Berlin, Palais des Beaux-Arts in Brussels, Palacio Euskalduna in Bilbao, Erfurt, Daroca, Gijón, Aranjuez…)

Alfonso Sebastián has made several recordings: Villancicos (carols) by Juan de Aragüés (Verso), works for two harpsichords by Luigi Boccherini (with Silvia Márquez). Also, with Los Músicos de Su Alteza he has recorded the Miserere by Nebra and La divina Filotea, as well as Villancicos by J.R. Samaniego, the opera Amor aumenta el valor by Nebra and Italian oratorios by Carissimi and Luigi Rossi for the French label Alpha.

Currently, and since 1999, Alfonso Sebastián is Professor of harpsichord and basso continuo at the Conservatorio Profesional de Música de Salamanca. He currently lives in Salamanca, Spain.