Essential oils or volatiles or ethereal oils are aromatic oily liquids obtained from various plant parts such as roots, leaves, seeds, stems and fruits. Due to the anti-bacterial, anti-viral, anti-fungal, medicinal and cosmetic propterties, essential oils are used for multi-functional purposes since the Middle Ages. Essential oils and their constituents are indispensable raw materials for the flavor and fragrance industries. Importance of essential oils supported by recent scientific reports is increasing day to day. Isolates and fractions of essential oils are used directly or in diluted forms in the flavour, food, fragrance, cosmetic, toiletry, fine chemical and pharmaceutical industries and for therapy. The isolation and identification of essential oil compounds from plants involves complex processes. In this review, we summarize the isolation and characterization of essential oil components using advanced techniques.