Recently, an immunocytochemical method using glutaraldehyde fixation and an antiserum developed against a GABA--glutaraldehyde--protein conjugate has permitted direct visualization of GABAergic structures in the brains of perfused animals. This paper reports a successful use of this technique on human temporal cortex fixed by immersion. The cerebral tissue was obtained from patients operated for focal epilepsy. GABA-positive somata, fibres and terminals are observed in all layers of the temporal cortex. Terminals are particularly abundant in the superficial portion of layer I and in layers II, III and IV. Dense plexuses of fibres are located in layers II, III, IV and VI and in the underlying white matter. Somata are found in all cortical layers and in the underlying white matter; they are round, oval, fusiform or triangular and exhibit a multipolar, bitufted or bipolar dendritic pattern. This technique for the visualization of GABAergic structures in the human brain may allow a better understanding of the pathogeny of epilepsy in which the GABAergic transmission has been implicated.