"What a Difference You've Made in My Life" is an inspirational song written by Archie Jordan and first made famous by two artists during 1977: teenaged Christian music singer Amy Grant and country music singer Ronnie Milsap.

Grant's version was included on her self-titled debut album "Amy Grant", which was sold largely in Christian bookstores and outlets. The song was released as a single to Christian-oriented radio stations, and helped Grant become well known in what was then a small subgenre of religious-themed music.

It was Milsap's version, however, that became better-known. It was released in November 1977 as the second single from the album It Was Almost Like a Song. The song soon scored the Billboard magazine Hot Country Singles chart and was his ninth No. 1 song on that chart. Milsap re-recorded the song for his 2009 country gospel album, Then Sings My Soul.

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