Renault S.A. is a French vehicle manufacturer producing cars, vans, buses, tractors, and trucks, and, in the past, autorail vehicles. Its alliance with Nissan makes it the world's fourth largest vehicle maker. Headquartered in Boulogne-Billancourt, Renault owns the Romanian Automobile Dacia and the Korean Renault Samsung Motors. is the current CEO. The company's most successful cars to date are the Renault Clio and the Renault Laguna, and its core market is Europe. The company is known for numerous revolutionary designs, security technologies and motor racing.