This is the third time that the Air Traffic Control Quarterly has published the best papers from the continuing series of USA/Europe Seminars on Air Traffic Management Research and Development. This Foreword reviews the selection process, provides a thumbnail of the key contributions of each paper, and then concludes with a short editorial in the context of these papers. The seminar, the sixth in the series, was held in Baltimore during June 2005. A total of 132 papers were submitted, and 69 of those papers were selected. The selected papers were divided into 10 tracks: