The review is concerned with electrophilic aromatic substitution. It discusses: - para enhancement in the case of aromatic ketones, sulfonic acids, alkylbenzenes, and nitroanilines or nitroarenes; - ortho enhancement in the case of phenols and aromatic ethers, arylamines and anilides, alkylbenzenes, benzoic acid, and a few miscellaneous types; - meta enhancement in the case of aniline and its derivatives, alkylbenzenes, aromatic ketones, substituted phenols, aromatic halides, naphthalenesulfonic acids, and [2.2]metacyclophanes; - the ortho effect.