This chapter describes general and specific detection and determination methods for amino acids and amines, often those designed for the detection and determination of specific compounds. The enantiomers are detected by irradiating with UV light, which causes them to be revealed as yellow-green fluorescent spots. When using fluorescence for the detection of amino acids a light source is generally used for the excitation of fluorophores. Electrochemical detection is a sensitive and specific method for compound with intrinsic electrochemical activity, but most amino acids with the exception of tryptophan, tyrosine, and cysteine are not electrochemically active within the useful potential range. The o-phthalaldehyde derivatization of amino acids is ideally suited to their detection in physiological fluids using liquid chromatography. The reaction of o-phthalaldehyde with primary amines and amino acids has been used under a variety of conditions for the formation of fluorescent products that can be detected in very small amounts.