There are two accepted mechanisms to explain the origin of runaway OB-type stars: the Binary Supernova Scenario (BSS), and the Cluster Ejection Scenario (CES). In the former, a supernova explosion within a close binary ejects the secondary star, while in the latter close multi-body interactions in a dense cluster cause one or more of the stars to be ejected from the region at high velocity. We present a non-LTE analysis of a sample of runaway stars observed with UVES, FEROS and the McDonald 2.7-m telescope. The runaways show no obvious abundance anomalies (e.g., N/Mg) when compared with stars in the open clusters. The runaways do show a spread in composition which reflects the Galactic abundance gradient and a range in the birthplaces of the runaways in the Galactic disk.

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