Publisher Summary This chapter presents laboratory techniques and working methods of liquid chromatography (LC). The selection of a liquid chromatographic mode, together with correct column packings, is the most important step in designing a separation process. For the selection of the LC mode (1) the molecular weight, (2) the solubility, and (3) the ionic character of a compound or a mixture of compounds to be chromatographed are taken into account. The detailed specification of reversed-phase chromatography (RPC) application depends on the polarity of the substances to be chromatographed. If an ionic sample is to be separated, the order of choice is (1) RPC with pH control, (2) polar bonded phase chromatography, (3) ion-pair reversed-phase chromatography (IP-RPC), and (4) adsorption chromatography. Higher molecular weight substances that are soluble in organic solvents are best separated by gel permeation chromatography by using an organic-swollen gel. The three optional modes of elution include isocratic, stepwise, and gradient. The selection of column packing techniques (dry and slurry packing) usually depends on the particle size.