It was originally released on Sub Rosa in 1999 and then re-released on Chicago indie Kranky in late 2002.

By the time of this recording, band members Adam Wiltzie and Brian McBride were residing in Brussels, Belgium, and Los Angeles, California, respectively.

It is reported that a vast proportion of this album was recorded through mail, with ideas being sent back and forth between the duo.

John Bush, writing for AllMusic, stated: Avec Laudenum moves at a glacier's pace and, slowly yet surely, calls to mind the glazed eye, vacant trance, and pure (temporary) euphoria of the heavy laudanum user.

"The Atomium," a three-part work, takes all of 16 minutes to gradually build from a series of softened drones into the exquisite ambience of an orchestra lulling heaven itself to sleep, only to halt the reverie by (just as gradually) introducing ominous backmasked guitars.