Dave Armstrong (b. July 30, 1958) is a prolific Catholic writer who maintains one of the most popular Catholic apologetics sites on the Internet, . Armstrong also runs a lively blog, (Latin for “Heart Speaks to Heart”).

Armstrong was born in Detroit, Michigan. He became an evangelical Christian in the 70's, and served as an evangelical campus minister for several years. He was also active in the pro-life rescue movement, where he began to associate regularly with Catholics. In 1991, after intensively studying Catholic teachings, he was received into the Catholic Church by Fr. John Hardon, SJ, the well-known catechist. Armstrong is married, and has four children. The family resides in the Detroit area.

Armstrong has become famous in the small but growing Roman Catholic apologist blog community for his rather long, and sometimes provocative, exchanges with Protestant apologists. Like any prominent controversialist, he has many vocal critics. Many readers,

In addition to his Internet activities, Mr. Armstrong is the author of several apologetics books, including: A Biblical Defense of Catholicism, The Catholic Verses, and More Biblical Evidence for Catholicism. He has also been a guest on the popular Catholic radio show, , and has appeared several times on radio shows hosted by Al Kresta, among others.