Four types of vocalizations uttered by the nocturnal Lizard Gekko gecko (the "Tokay'') are described. A bark of intimidation, distress calls, a short not very intense call, apparently related to sexual inter-action, and a long, complex sequence. This "long sequence'' is considered as a territorial proclamation which functions also as a mating-call. This call has been analysed in detail with special emphasis on the intra-individual variations. The mean duration of this sequence is 22.3 s, the intensity is 70 do at lm and the maximum of energy is between 300 and 400 Hz. This sequence is composed of three phases. The first one consists of several "roulades'', the second, of bi-motifs which sound like two syllables tok-kay, and the third, not always present, is a kind of "rattle''. The number of motifs and the occurrence of the 3rd phase vary in the sequence of an individual, but the duration of the motifs is relatively stable.