The document presents an updated and revised Standard for Clinical Pattern Electroretinography (PERG) testing by the International Society for Clinical Electrophysiology of Vision (ISCEV). This update replaces the 2013 version and includes changes to promote consistency in methods for diagnosis and monitoring, while adapting to evolving clinical practices and technology. Key revisions include expanded guidance on large stimulus fields, simultaneous PERG and pattern visual evoked potential (PVEP) recording, baseline drift correction, and consistent ambient room lighting. The standard aims to facilitate good quality recordings and inter-laboratory comparisons. The document also provides detailed guidelines on equipment, electrodes, stimuli, recording methods, and reporting specifications, emphasizing the importance of stable baseline voltage, artifact rejection, and proper calibration. Additionally, it discusses the clinical applications of PERG, including its use in assessing macular cone and retinal ganglion cell function, and provides recommendations for patient preparation, fixation, and refractive correction. The standard includes optional methods for large field PERGs and simultaneous PERG and PVEP recordings, as well as non-standard methods such as steady-state PERG and large check widths.The document presents an updated and revised Standard for Clinical Pattern Electroretinography (PERG) testing by the International Society for Clinical Electrophysiology of Vision (ISCEV). This update replaces the 2013 version and includes changes to promote consistency in methods for diagnosis and monitoring, while adapting to evolving clinical practices and technology. Key revisions include expanded guidance on large stimulus fields, simultaneous PERG and pattern visual evoked potential (PVEP) recording, baseline drift correction, and consistent ambient room lighting. The standard aims to facilitate good quality recordings and inter-laboratory comparisons. The document also provides detailed guidelines on equipment, electrodes, stimuli, recording methods, and reporting specifications, emphasizing the importance of stable baseline voltage, artifact rejection, and proper calibration. Additionally, it discusses the clinical applications of PERG, including its use in assessing macular cone and retinal ganglion cell function, and provides recommendations for patient preparation, fixation, and refractive correction. The standard includes optional methods for large field PERGs and simultaneous PERG and PVEP recordings, as well as non-standard methods such as steady-state PERG and large check widths.