Analytical method is the one by which we can easily quantify the drug in its form or in pharmaceutical dosages form. With the growth of pharmaceutical industry during last several years, there has been rapid progress in the field of pharmaceutical analysis to provide simple analytical procedure for complex formulation. For new drugs, sometimes the unavailability of analytical procedure makes necessary to develop new analytical methods for such drugs. High performance liquid chromatography is an important qualitative and quantitative technique which is widely used nowadays for estimation and quantification of a wide range of samples.This book presents method development and validation protocols for estimation of drugs in fixed dose drug combinations as well as for excipients such as food colorants in food stuffs.