The document discusses chromatographic techniques for estimating plant hormones, detailing the history, principles, and methods including high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). It highlights challenges in accurately extracting and quantifying various hormones, as well as recent advancements that enhance the efficiency and reliability of these analyses. Applications of these methods in plant hormone research and analyses, particularly for indole-3-acetic acid and abscisic acid, are also covered.