Walter Castro He started studying bandoneon with professor Domingo Mattio, later he continued with professors Julio Pane and Nestor Marconi.

In 1985 he created The Sexteto Menor later known as Sexteto Sur. At the beginning of 1990 he plays in Osvaldo Pugliese´s Orchestra and in that same year participates in the Orchestra of Horacio Salgan in a Show called "Images" in the Plaza Center (Complejo La Plaza). He starts touring through the interior of Argentina and abroad.

In 1993 he wins the contest for Bandoneon Professor and Group practices assistant of the "Popular Music School of Avellaneda" (working as such as Assistant of Orlando Tripodi, Rodolfo Mederos and Rodolfo Alchourrón. He participates in different Music Shows in which he occasionally plays with Atilio Stampone, Osvaldo Berlingieri, Virginia Luque, Raúl Lavié, etc.

In 1995 he participates of the quintet that plays for the singer Adriana Varela. In the same year he joins the Pablo Ziegler´s Quintet for New Tango".

In 1996 he performs in the Luna Park with Liza Minelli and Julio Bocca.
In the same year he forms part of the quintet 5/4 (cinco cuartos) and with this group he records a CD with singers from Brazil.

In 1998 he records with Pablo Ziegler and The Orpheus Chamber Orchestra a CD called "Tango Romance" with BMG/RCAVICTOR New York.

In 1999 he records another CD called "Pablo Ziegler Quintet for New Tango" for the same record label.
In that same year he played as first bandoneon in a Show in "Armenonville" in The Alvear Palace Hotel in Buenos Aires.
He also has made several recordings with several performers and in October same year a CD of the instrumental group formed in 1996 with three friend musicians came out by Melopea label. This group is called "Presencia Tanguera" and its members are Angel Bonura, Hernán Posseti and Germán Martinez.

In January 2000 he participates of "Tango Sinfónico" in Sydney (Australia) together with Miguel Angel Zotto and Pablo Ziegler playing in the "Sydney Opera House Concert Hall". Later he plays with Tango x 2 in Europe. In April tours by Italy, Denmark, Germany, Switzerland and Austria as a guest of The "New Tango Duo" Pablo Ziegler and Quique Sinesi.
He later plays in Buenos Aires (Argentina) at El Club del Vino with singer Julia Zenko.

He then plays with the Royal Philharmonic of London in San Pablo, Brazil, and later plays at the Jazz festival “De los 7 Lagos” in Bariloche, Argentina and then at different places in Buenos Aires as The Teatro San Martin, La Universidad de Ciencias Empresariales y Sociales, Opera Prima, and National Radio all with Pablo Ziegler.
On the 28th and 29 December plays with Ziegler´s Quintet at Orvieto (Italy) in The Festival Umbria Jazz Winter in a show called Tango "Swing and Passion", on the 30th with Ziegler, Ragazzi and Paquito D´Rivera and on the 31st with Ziegler and Ragazzi.
January 2001 participates with Ziegler´s Quintet in Jazz festival in Punta del Este, Uruguay and in February together with Miguel Angel Zotto and Pablo Ziegler plays in Sydney (Australia) three concerts with the soloists of The Sydney Symphonic Orchestra at “The Sydney Opera House Concert Hall”. He then participates with Ziegler´s quintet in “The Buenos Aires Tango Festival “ on March 4th and plays in The Terrace of the Centro Cultural Recoleta in Buenos Aires (Argentina)
On March 15 and 16 he plays with the Stavanger Symphonic Orchestra in “The Stavanger Concert Hall”, in Bjergsted Music Center in Stavanger, Norway with Ziegler .
At the end of the month he starts a tour with The New Tango Duo as guest with Pablo Ziegler and Quique Sinesi by several cities in Europe such as: "Jazzhouse" in Copenhagen, (Denmark) "Musikföreningen Piektrum" in Lund and "Nefertiti" in Göteborg (Sweden) "Alter Schiachthof" in Soest, "Passionskirche" in Berlin, "Waschhaus" in Potsdam, "Domicil" in Dortmund, "Hotel Bayerischer Hof-Night Club" in München and "Karistorbahnohof" in Heidelberg (Germany) "Moods im Schiffbau" in Zurich (Switzerland), "Printemps Musical Festival de Luxembourg " (Luxemburg), "Scen Wien" in Wien, (Austria) and "Teatro Sociale" in Cremona (Italy)
Then on July, Friday 6 and 13th he plays with Ziegler´s “New Tango Trio” at “Tobago Cigar & Arts Cafe”. . He then travels to Israel performing with Ziegler´s Quintet, at “The Rappaport Hall” in Haifa, at The Opera House Performing Center in Tel-Aviv, and at “The Jerusalem Theatre” in Jerusalem.
He returns to Buenos Aires to perform with Ziegler´s New Tango Trio (piano, bandoneon and guitar) at Notorius in what was called "Música Notoria" on December, Friday 6th and Saturday 7th.

2002 He participates of the 4th Tango Festival held in Buenos Aires were he plays also with Ziegler at The Teatro Presidente Alvear. He then starts a tour as a guest with The New Tango Duo through Potsdam, Berlin, Munich, Heidelberg, Puchheim, Neuburg, Frankfurt and Bonn (Germany) and through Graz and Salzburg in Austria.
He travels to Italy in the month of May for rehearsals and Presentations at Ravenna Festival (Alighieri Theatre) Three Performances of "Operita María de Buenos Aires with Ziegler as Maestro Concertatore and Musical Director on June 13, 14 and 15. Also at the Teatro Comunale de Bologna on June 18th, 19th, 20th, 21st, 23rd, 26th and 28th with the same Play. After these successful shows he starts a tour with Ziegler´s Quintet on June 30th by Schauspielhaus in Zurich, Switzerland, then in July at Kassel Kulturzelt, and Kiel Jazzbaltica, both in Germany, then he presents himself at Jazz house (Copenhagen Jazz Festival) in Denmark, then at (Jutters Festival) in wijk Aan Zee in Holland, at the London Tate Modern in London England, at the Klaversommer in Munich and at the (Jena Festival), both in Germany.
In October and November plays with Ziegler at El Argentino and Teatro Hindú Club in Buenos Aires , Argentina.

2003 Starts playing with Ziegler at the Lapataia Jazz Festival in Punta del Este, Uruguay, then The Tango Festival at Teatro Metropolitan, Buenos Aires, Argentina, then also with Ziegler´s Quintet in Manchester, England, and a tour with Ziegler and Sinesi through Germany , Switzerland and Austria.
Goes on playing with Esteban Morgado Quartet, Adriana Varela, and Juan Dhartes.
Then travels to Rosario, Santa Fe Province in Argentina to play with the Orquesta de Cámara Municipal de Rosario, with Ziegler, at El Teatro “El Círculo”