Brennan released her first solo album in 1992, "Máire", on Atlantic Records. "Misty Eyed Adventures" on BGM followed three years later. In 1998, Brennan signed with Word Records and released "Perfect Time", and "Whisper to the Wild Water" a year later. The album was nominated for the Grammy Award for Best New Age Album in 2001. Brennan is managed by her husband Tim Jarvis and her brother Leon Ó Braonáin. Her music is usually classified as New Age or Celtic. She accepts the Celtic label, but has at times indicated a slight discomfort with being seen as "New Age" as much of her music is strongly Christian, with several of her songs centring on maintaining a relationship with Jesus. Some of her songs show influences from her Roman Catholic upbringing or seem relational due to her own views concerning Mary, the mother of Jesus.