The Test Methods in this edition of the Technical Manual were current as of May 2007. New methods that have been added and other important changes made since the last issue are summarized on page 14. AATCC test methods are developed by research committees through extensive investigations and interlaboratory comparisons, often covering several years of work. Simplicity, reproducibility, applicability, cost of performing the test and the time required to perform the test are all important considerations in each development. Before a method is published in the TECHNICAL MANUAL, it must be approved by the responsible research committee, reviewed by the Editorial Committee and approved by the Technical Committee on Research (TCR).