The Louisville Combustibility Test (LCT) is a simple method for the measurement of the rate of burn of cigarette paper, which was described by the author at the 1997 CORESTA Meeting in Hamburg. There has been much interest in this test because of the need of the Roll-Your-Own tobacco industry to have a quick, simple and reproducible method for the classification of cigarette paper leaflets into two classes to support CORESTA Recommended Method N° 44; the determination of tar and nicotine in fine-cut tobacco products. The Association of the European Cigarette Paper Converting Industry, ECPCI, has carried out a study of the LCT method with the objective of evaluating it across a wide range of RYO cigarette paper leaflets which represent over 95% of the European market. Thirty leaflets were sampled and tested by five laboratories using version 3 of the LCT method. The thirty leaflets covered the full range of cigarette paper burn rate from 30 sec to over 90 sec and four of the leaflets were self-extinguishing. The results to be presented show that if a breakpoint of 60 sec is assumed between the two classes of cigarette paper leaflet then thirteen of the leaflets were found by all five laboratories to be equal to or less than 60 sec. Fifteen of the leaflets were found by all five laboratories to be greater than 60 sec. Only two leaflets, very close to the breakpoint, were indeterminate.This study has shown that RYO cigarette paper leaflets can be readily and reproducibly classified into two classes using the LCT method. The LCT method is very simple to carry out and apply and does not require any complex techniques or special apparatus only available in specialist laboratories.