Methods are provided for monitoring and controlling a chemical mechanical planarization (CMP) process. Relationships between motor torques and CMP process parameters are determined and utilized to provide a basis for monitoring and controlling the CMP process. Motor current measurements obtained during the CMP process are converted to motor torques to provide for use of the relationships in monitoring and controlling the CMP process. The motor current measurements and relationships are also used to determine and monitor a coefficient of friction present during the CMP process.