Únicas was the first Azúcar Moreno album since 1990's Bandido not to be partly or entirely recorded in the United States, but in Spain and Italy, and it also features strings by the Prague Philharmonic Orchestra. Únicas however saw the Salazar sisters continuing their longtime and successful collaboration with Spanish singer and composer Miguel Gallardo, this time also in the role as main producer, assisted by Bruno Zuchetti and Danilo Ballo in Milan and Rome. The album also featured further songwriting contributions from the team Pedro del Moral and David Ferrero, who previously had remixed several of their hits like "Amén", "Abracadabra", "Mamma Mia", "Olé" and "Mecachis!".
The lead single from the album was "Besame", also released as an extended dance mix, followed by a cover of The Champs' 1958 rock hit "Tequila" and the melancholy ballad "Volvería A Nacer". The album continued the duo's fusion of rumba flamenca and contemporary urban dance music genres like disco and R&B, the track "Que Me Quiten Lo Bailao" also incorporates influences from Brazil and "Habbibi Te Quiero" ("Habibi" meaning "darling" or "my beloved" in Arabic) again features rhythms and sounds from the Middle East. The album closes with the high camp anthem "Divina De La Muerte", with the verse explaining that there is nothing better to cheer up a dull day than going on a shopping spree, and the sisters namedropping their favourite designer brands; Dolce & Gabbana, Chanel, Prada, Shiseido, Gucci, Louis Vuitton, Galliano, Dior, Moschino, Valentino, Escada, Versace, Cartier, Cavalli etc. The chorus goes on to proclaim; "Yo soy una chica con suerte - estoy divina de la muerte!" (Translated: "I'm a lucky girl - I'm deadly divine!")
Únicas was only a moderate commercial success compared to Azúcar Moreno's previous efforts, selling some 100,000 copies in their native Spain. Unicas was also one of Sony Music Entertainment's 2002 releases known to be affected by the company's copy protection software, both the album cover and the CD itself clearly state No reproducibile en PC/MAC.
Únicas came to be Azúcar Moreno's final album with Miguel Gallardo, who over a period of some ten years had written, co-written, produced or co-produced around twenty-five songs for the duo, including some of their greatest hits. After a long struggle with cancer Gallardo died in 2005.
Miguel Angel Collado - musical arranger, musical director
Emanuele Ruffinengo - production coordination, musical director, realization
Ludovico Vagnone - recording
José Peña Engineer - digital editing, mixing
Riccardo Dacunto - recording
Fernando Chávez - recording
Sabino Cannone - mixing, sound design
Mark Bishop - sound design
Jose Vinader - engineer
Francisco Gude - engineer
Marcos Liviano - assistant
Michael Hradisky - assistant
Antonio Baglio - mastering engineer
Carlos Martin - graphic design, art direction
Juanjo Manez - stylist
Adolfo Cabiedes - interpretation
Joan Alsina - photography
Recorded at Zodiak Studios and Altavox Studios (Milan), Trendy Studios (Rome), Ludus Studios & Trak Studios (Madrid). Strings recorded at Smecky Studios (Prague).
