Many children and adults appear to have difficulty listening despite that their hearing thresholds are within the normal limit. Understanding rapid speech, following complex instructions, and listening in the presence of background noise represent some of these difficulties. The process of "what we do with what we hear" simply explains the (central) auditory processing. (Central) Auditory Processing Disorder ([C]APD) has been observed in diverse clinical populations, including those with suspected or diagnosed central disorders (e.g., dyslexia, attention deficit disorder hyperactivity disorder [ADHD], aphasia, and Alzheimer's disease). (C)APD has been researched for decades; however, the awareness of this disorder is still limited, and more children go undiagnosed. This article provides a fundamental understanding of (C)APD and reviews (a) the relationship between (C)APD and some disorders (i.e., otitis media, dyslexia, ADHD, and autism), (b) the role of audiologists and speech-language pathologists, (c) diagnostic models, and (d) intervention strategies.