Hearing aid processing no longer operates under the assumption that the real-world listening environments are represented by simple laboratory test conditions, such as the talker of interest is in front with noise behind, or even that there is only a single talker of interest. In addition, the driving philosophy has shifted from treating a single complaint (e.g., understanding in noise) to holistically treating individuals across the full range of their real environments and experiences (e.g., connecting to an auditory world).