Northern Ireland have never before won their first three matches in a World Cup or European Championship series but this victory puts them right on course for the first major finals for 30 years.
The visitors enjoyed important early territory with the tireless Lafferty worrying home goalkeeper Orestis Karnezis.
Oliver Norwood’s third corner fell kindly for Ward 12 yards out, and his sclaffed connection clipped off Loukas Vyntra to give Karnezis no chance (9).
Greece’s response was untidy, with over-hit passes and snatched shots, and Roy Carroll had little to do in a stadium where he played with Olympiakos for three seasons.
When Georgios Samaras sprang Nikos Karelis through the middle, Carroll raced out of his area and did enough to put him off as the lofted shot drifted wide of the unguarded net.
Moments before the break, Lafferty bulldozed his way down the left and thumped a shot off the face of the crossbar from a tight angle.
But the Norwich man was not to be denied as he skipped clear of Kostas Stafylidis on the halfway line and kept his head with a composed finish from 18 yards (51) to extend the advantage.
If the Northern Ireland side were braced for a furious response, it never materialised – a flurry of cynical fouls from the Greeks underlining their mounting frustration.
After 62 minutes, Tachtsidis finally forced a decent save out of Carroll with a skidding drive but Michael O’Neill’s side’s defensive resolve never wavered as they held out comfortably for another memorable success.