Thankful is Mary Mary's first album. This project contains both the smash crossover hit "Shackles (Praise You)" (which was a top ten hit in 7 countries) and the single "I Sings," which was also a significant hit—although it did not match the success of its predecessor. The album established Mary Mary as one of the leading artists in contemporary Christian music, and won the duo a Grammy. The album peaked at #1 on the Billboard Gospel Album chart, #22 on the U.S. Billboard Top R&B/Hip-Hop Albums chart, and #59 on the U.S. Billboard 200 chart, and it was certified Platinum after sales exceeding 1.2 million in the U.S.