Lacey Nicole Mosley (born September 4, 1981) is the lead vocalist and main lyricist for Texan alternative metal band Flyleaf.

Lacey Mosley was born in Arlington, Texas, to a single mother of six. The family was poor, and when ends didn't meet in one place, they'd move to another. Between moving and fights with her mother, what Lacey describes as "a war zone going on at home", she began dabbling in drugs.

"The first time I ever did drugs, I was ten years old. I kind of kept it a secret from people at school, and I always had a thought that it was wrong, you know. I kinda knew it was wrong. But, then, when I was thirteen, I found these other people that did drugs and I got even worse into it. It was like whatever I could do, I would do it, you know? I was trying to figure out who I was, and anything to separate me from my family, or to separate me from my situation at home, was awesome, was good to me."

—Lacey Mosely

Lacey received a bass guitar at fourteen, and began playing Green Day and Nirvana songs. At sixteen, the fighting between Mosley and her mother became too intense and the police were forced to step in. She then moved to Gulfport, Mississippi to live with her grandparents. While going to school at Gulfport High School, she joined a band that was searching for a bass player. She continued on to sing for the band, writing lyrics, and playing guitar. Lacey decided to quit the band because of communication problems and the amount of negativity she felt coming from the music.

As Lacey grew more depressed, she became more outspoken in her atheism. After living in poverty with her mother and continuing on to live with her wealthy grandparents, she felt dissatisfied with life.

"It's funny, 'cause I kind of had the two extremes - I was really poor, and then I went to live with my grandma, who was really rich, I remember thinking, 'Is this it? Is this all life has to offer? And if it is, I'm not satisfied with it.' And I don't believe what the world has to offer you is enough."

—Lacey Mosely

At 16, after leaving her family and leaving drugs, Lacey experienced what she described as a "nervous breakdown". She cut off her hair and began considering suicide. Her grandmother became distressed and urged Lacey to attend church. Her experiences in church caused her to renounce her atheism and became a Christian.

She was married briefly before a divorce, and moved to Temple, Texas. There she met drummer James Culpepper. They soon teamed up with guitarists Jared Hartmann and Sameer Bhattacharya, whose own band had recently broken up. Bassist Pat Seals came into the picture, and their first time playing together is what Lacey describes as "something amazing." They then proceeded to create the band she's currently in, Flyleaf (previously Passerby).