ASTM Committee D35 on Geosynthetics has reapproved Standard D6523, “Standard Guide for Evaluation and Selection of Alternative Daily Covers (ADCs) for Sanitary Landfills,” as D6523-00(2009). This guide provides information which the regulator/permit officials, engineers, waste disposal operators, and others will find helpful to (1) understand and distinguish between the many choices available; (2) understand the performance feature considerations for living up to EPA regulations for landfill daily covers, and (3) understand the various requirements and differences for putting these covers into practice at landfills.