Geo-political volatility is Nihat Gokyigit's bread and butter. As head of Tekfen Holding A.S., Turkey's foremost oil and gas pipeline constructors, the silver-haired Mr. Gokyigit often operates in a risky political environment. Rumbling through maps and feasibility studies in his woodpanelled office overlooking the Bosphorus, Mr. Gokyigit exudes an air of confidence as he discusses plans for pipelines that would soon ferry Central Asian and Caucasian oil and gas to western Europe. "Whatever happens, one thing is certain," he says. "Turkey will be at the crossroads of the pipelines."