Giorgio Gaslini started early: performing at 13, recording with his own trio at 16, then formal training at the Milan Conservatorio in piano, composition, and conducting. That classical grounding never left his playing. He built his career on the premise that 20th-century composition technique and jazz improvisation belonged in the same room, not in separate ones, a fusion he named "total music."

The clearest demonstration came on February 4, 1966. Don Cherry had read about Gaslini in Melody Maker and turned up at his home in Milan with Steve Lacy and Gato Barbieri in tow. Gaslini's record label gave him 48 hours and a midnight deadline; he wrote a four-movement suite overnight and recorded it the next day in a single ten-hour session. The lineup also included Gianni Bedori, J.-F. Jenny-Clark, Kent Carter, Aldo Romano, Franco Tonani, and a 26-year-old Enrico Rava on trumpet. Down Beat gave the resulting record, Nuovi Sentimenti, five stars and called it the best Italian work of the year.

Film scoring ran alongside the jazz career from early on. Gaslini scored Michelangelo Antonioni's La Notte in 1961 and won the Nastro d'Argento, Italy's Silver Ribbon award, for it in 1962. He wrote music for Dario Argento's The Five Days in 1973, then attempted a score for Argento's Deep Red in 1975 that was largely replaced by the band Goblin, keeping only three of Gaslini's themes in the theatrical release. Across his career he composed more than 40 film scores, most for Italian cinema.

In 1972, Rome's Santa Cecilia Academy of Music gave Gaslini its first jazz course, the first academic jazz program in Italy, which he held through 1973, a generation before conservatory jazz departments became standard anywhere in Europe. Between 1991 and 1995 he composed for the Italian Instabile Orchestra, the collective whose members included clarinetist and saxophonist Gianluigi Trovesi.

He kept working at the edges of the American avant-garde well into his later decades. In 1990, in his sixties, he recorded Ayler's Wings, solo-piano transcriptions of Albert Ayler. In 2003, in his seventies, he recorded an entire album of Sun Ra compositions, Gaslini Plays Sun Ra, released in 2005. He passed away on July 29, 2014, at 84, in Borgo Val di Taro, in the hills above Parma.

Gaslini called his own style "total music," a direct fusion of 20th-century classical composition techniques (serialism, aleatory writing) with jazz improvisation, rather than keeping the two vocabularies in separate pieces. That instinct shows up across his catalog: solo-piano records built entirely around another composer's material (Monk in 1981, Ayler in 1990, Sun Ra in 2003), large-scale sacred and symphonic works late in his career (Sacred Concert/Jazz Te Deum, 2002), and film scores that treat orchestral and jazz-ensemble writing as the same job. His discography also runs unusually deep into Italian film and library music, both as a credited composer and as a heavily sampled/compiled source for soundtrack anthologies decades after the fact.