This review critically assesses the derivatization techniques employed in sampling and detection of carbonyl compounds in air. We explore the most common techniques reported for the collection of vapor- phase carbonyl compounds by focusing on the hydrazine-derivatization techniques developed with the aid of diverse sorptive media [solution (e.g., in impingers), solid sorbents, solid-phase extraction, solid-phase microextraction, and denuder, or other approaches]. We discuss the advantages and the disadvantages of each sampling and pretreatment option for key carbonyl compounds with reference to measurement data obtained under laboratory and field conditions.