As the sophistication and adaptivity of hearing aid technology increases, audiologists must use verification strategies that accurately and efficiently assess those aspects of amplification. Once the clinician selects appropriate devices, the gain and frequency response of the hearing aids should be set to ensure audibility of speech over a range of input levels, and the hearing aid gain, maximum output, and additional features should be verified. Probe microphone measures completed with speech signals at multiple intensity levels provide the most accurate assessment of hearing aid gain characteristics. Maximum output should be verified to ensure that the hearing aid is adequately limited at high intensity levels. When real-ear measurements are not practical, RECD measures are an acceptable alternative. Without probe-microphone verification, significant errors are likely, and because acoustic access to speech and language for infants and children is essential for development, individualized verification is essential for this population.