The most important considerations for rolling plate and strip are size control to obtain the target dimensions, and profile control to obtain flatness. Of the dimensions of flat rolled products, the target width and length can be obtained by shearing and cutting the surplus portions after rolling. However, the rolling operation itself is the sole and final means of ensuring the target thickness and profile. With a unit coil weight of 40 tons, a hot rolled coil 3.2mm in thickness and 1m in width has a total length of 1,600m; a cold rolled coil 0.8mm in thickness and 1m in width has a total length of 6,400m. The current tandem hot strip mills or tandem cold rolling mills can roll coils of these sizes in about 1 to 3 minutes. According to the present standard, the thickness variations in the longitudinal and width directions of the coil are within plus or minus tens of micrometer for hot rolled strip and several micrometers for cold rolled strip, as shown in the figure. High gauge accuracy can now be maintained over the whole length of a coil as a result of accurate prediction of the rolling force from rolling theory, the improved accuracy of the elastic deformation curve of the mill based on deformation analysis, and the practical use of high-level computer control techniques with high-sensitivity sensors and quick-response actuators. Progress in theory, operational techniques, and equipment as an integrated system is expected to lead to further improvements in accuracy.