Nollman and his cohort took a considered approach to developing sonic relationships with the orcas and other animals they encountered, always keeping a respectful distance as they found one another with their ears. Orcas' Greatest Hits collects hydrophone recordings drawn from over 60 hours of interspecies collaboration recorded between 1985 and 2002, showing the playful ways in which Nollman engaged the orcas from the portable studio floating above their home. What we hear is the focused listening by the cetaceans and humans as they search out sonic space among one another, finding in that dialogue potential common ground for deeper understanding.