This is a sixth paperback printing of Decision at Delphi by Helen MacInnes, published in 1962 by Crest Books.

From the publisher:

Just another routine overseas assignment. That’s what successful young New York architect Ken Strang thought when a national travel magazine sent him to Europe to sketch Greek ruins.

What he did not know, until it was too late, was that from the moment he boarded the ship, he had become the pawn in a murderous game of international intrigue.

To Strang, danger was no object. He could take care of himself, but he had reckoned without Cecilia, his beautiful photographer. When he fell in love with her, he gave his enemies the one weapon they needed.

..........................

Shipping combined for multiple purchases.  Delivery confirmation included on all domestic packages.