Thalía | Greatest Hits is the first compilation album by Mexican pop star Thalía. Released on February 10, 2004, the album features 14 singles from her five previous albums of original material for EMI Latin (it does not include any material from before 1995, nor from her various remake and remix albums), plus two previously unreleased songs "Acción y Reacción" & "Cuando Tu Me Tocas". All of the songs appear in Spanish, including those originally released in English.
In April and May 2004, Thalía toured the United States and Mexico on her High Voltage Tour. This marked the first time Thalía toured the US.
In the United States the album sold 50,000 copies after one month of its release, according to Nielsen SoundScan. In Mexico the album was certified gold.
"Acción y reacción": The song was previously unreleased, written by Estéfano and Julio Reyes and produced by Estéfano. This track was recorded during the Thalía Sessions, but didn't make it. So the unfinished demo was leaked in May 2002, and it had good reactions in the fans, Thalia decided this track should be re-recorded and re-arranged. The mastered version became included on the Greatest Hits album. This song talks about Thalía and Tommy Mottola's relationship. The music video contains footage from Thalía's "High Voltage Tour" in the United States and Mexico. It mixes images of her performances and of her fans when they were waiting in the concert's queues. The video was officially released by the TV Magazine Primer Impacto.
Greatest Hits Videos is a DVD release of 16 Thalia's music videos. It was released in 2004 and was certified Gold in Mexico and Platinum in Argentina. The DVD does not contain all of Thalía's videos, leaving out videos such as: "Viaje Tiempo Atrás", "Mujer Latina (European Version)" and all her videos from the first three albums,released by Fonovisa Records.In the United States the album came with 4 bonus videos.