Long latency brain potentials were evoked by infrared laser stimuli (LEPs) applied to the right forehead in order to activate the thinnest cutaneous A-delta afferents of the upper branch of the trigeminal nerve thus inducing a painful sensation. Ten healthy male subjects participated in 4 identical subsequent sessions, one week apart, receiving 4 blocks of 40 stimuli each. This way the individual trigeminal LEPs, as well as their inter- and intraindividual reliability were determined. Five major components could be identified, denoted by polarity and peak latencies: N150, P230, N300, P360, N480. The LEP waveforms were found to be highly stable within subjects, peak latencies varied by less than 5%. Great variation in waveform appeared amongst subjects, peak latencies varied by more than 15%. The last two components exhibited the largest variability and were not identified in all subjects.