Linguaphone allTalk is a series of audio-only courses developed by Linguaphone. It's primary difference from an audio course like Pimsleur is that the allTalk course has a plot -- generally, an English speaker arrives in the country where the language is spoken and learns the language bit-by-bit from their local business contacts.

The other major difference is that the allTalk courses contain specific grammar lessons, verb drills, and exercises, rather than relying on the normal "this just sounds right" approach of Pimsleur and Assimil.