The two destructive earthquakes of 1995 in Greece, the 13 May, Ms=6.6, Kozani-Gr evena and the 15 June, Ms=6.2, Aigion events provide an interesting material for analy zing problems related to the identification of precursors and to the efficiency and usefullness of prediction. The Kozani earthquake was preceded, within 30 minutes, by 5 foreshocks with magnitude greater than 3.5 (Papazachos et al., 1995). We relocated these events with respect to each other, showing that they are clustered within less than 2 km, at about 5 to 10 km to th e S-SW from the mainshock epicenter. This size of foreshock clustering correctly fits the correlation law with the mainshock magnitude obtained by Dodge et al. (1996) for Californian earthquakes. These foreshocks led to people leaving their houses, which explains the absence of any casualties, despite the partial destruction of several villages. The possibility of issuing predictions in this area from the observation of earthquake clustering is analyzed in light of the seismicity observed during the last 15 years. A prediction has been issued by the VAN group before this earthquake, based on SES records at the IOA station, on the 18-19 April 1995, which is considered by VAN as a su ccess (Varotsos et al., 1996a), but is in fact a failure to predict (Geller, 1996). This SES was also recorded by a magneto-telluric station installed by IPGP, a few km from IOA (Gruszow et al., 1996). These authors suggest an artificial origin of the SES, but could not track it. Simple amplitude estimates shows that a local, natural source such as an electrokinetic effect is unlikely, and that a remote electrokinetic source in the epicentral area can be even more confidently rejected. Another SES on VAN's network (VOL station, 30 April 1995) led the VAN group to predict an earthquake outside the IOA sensitivity area (IOA did not record any anomaly), and to announce a success when the Aigion earthquake occurred (Varotsos et al., 1996a); however, this event was located inside the IOA sensitivity area, and the prediction was hence a failure (Wyss, 1996; Bernard et al., 1997). Furthermore, at the time of this SES, no ground deformation was observed above the noise level of a few $10^{-8}$ at the IPGP/NTUA Galaxidi geophysical observa tory, 20 km from the hypocenter, leading Pinettes et al.(1996) to conclude that the electrical source of this SES is most probably located near VOL, 100 km away, whatever its correlation with the earthquake.