The overall aim of this study was to provide clinicians with comparative data on the resistance to orthodontic sliding associated with currently available ligation methods. A wide range of commonly used ligation methods were assessed using a novel standardized friction testing procedure which closely simulated the oral environment and orthodontic tooth movement. Among the eleven ligation methods tested three were self-ligation bracket systems, seven were elastomeric modules and a stainless steel ligature. Statistical analysis revealed that there were significant differences between almost all of the methods of ligation in the mean force required to overcome the resistance to sliding.