Fischer attended Michigan State University, studying composition and music theory under Herbert Owen Reed and graduating cum laude with his Bachelor's degree in 1951, followed by a Master's in 1955. (He received an Honorary Ph.D. from Michigan State in December 1999.) Shortly after graduation, Clare Fischer began working with The Hi-Lo's band, as a piano accompanist and subsequently an arranger on several [l=Columbia] albums. Circa 1957, Fischer arranged the [r=2534133] album for renowned jazz trumpeter Donald Byrd (unreleased for the next 25 years), followed by small ensemble arrangements on [m=421677] by Dizzy Gillespie, released by [l=Verve Records] to critical acclaim in 1960. He also collaborated with a prominent vibraphonist Cal Tjader on several records on [l=Fantasy] and Verve.

In 1962, after relocating to Hollywood and signing his first record deal with [l=Pacific Jazz], Fischer released a debut album under his name, [m=449642]. He soon established a reputation in Brazilian music, presenting [m=489236] duo with saxophonist Bud Shank, with "Pensativa" widely adopted as a jazz standard. He also arranged [m=300732] by pianist George Shearing for [l=Capitol Records]. In the early-to-mid 1970s, Fischer began commissioning orchestral and string arrangements for pop-oriented R&B, funk, and disco acts, starting with Chaka Khan's band Rufus co-founded by his nephew [url=https://discogs.com/artist/284968]André[/url] and subsequently working with The Jacksons, Earl Klugh, Switch and DeBarge, Atlantic Starr, and Shotgun. Clare also wrote music for commercials and the film industry, collaborating with Henry Mancini and recording piano on Lalo Schifrin's [url=https://discogs.com/master/1137111]Boulevard Nights[/url] soundtrack, among others.

In the late 1970s, he started a new band, [a=Clare Fischer & Salsa Picante], leading on electric piano and featuring his son [url=https://discogs.com/artist/436604]Brent[/url] on electric bass. Their debut [m=601542] LP on [l=Pausa Records], featuring an [url=https://discogs.com/artist/3629180]eponymous vocal quartet[/url], earned three Grammy nominations and won the "Best Latin Recording" award in 1981. Fischer then formed [url=https://discogs.com/artist/3982940]Latin Jazz Sextet[/url], winning another Grammy for "Best Jazz Vocal Performance" with [url=https://discogs.com/master/1200759]Free Fall[/url] LP in 1986. He established and directed several other prolific ensembles, including his [url=https://discogs.com/artist/1970936]Big Band[/url] and [r=12387283] with 20+ brass instruments.

Fischer began collaborating with Prince in 1985, contributing orchestral arrangements on [m=16132]. In the next twenty years, they partnered on several studio albums and film soundtracks, including [m=52497], [url=https://discogs.com/master/52430]Batman[/url], [m=22447], [m=97264], [url=https://discogs.com/master/233491]Girl 6[/url], and [m=109262]. Clare Fischer also formed and conducted The NPG Orchestra, which recorded Prince's sole classical music experiment, [m=778640] ballet, and contributed to solo projects by Prince's protegés on [l=Paisley Park] and [l=NPG Records], including Jill Jones, Eric Leeds, [url=https://discogs.com/artist/148601]The Family[/url] band, Chaka Khan, Larry Graham's GCS, Támar Davis, and Bria Valente.