After a little more than a year in the job, Malcolm O’Neill, assistant secretary of the Army (Acquisition, Logistics and Technology) and Army Acquisition Executive, has tendered his resignation for personal reasons, effective June 3, sources said.

It is likely that Principal Deputy Heidi Shyu, responsible for research and technology for the ASA (ALT), will at least temporarily take the reins. Shyu worked at Raytheon [RTN] before taking her job with the Army last year.

In a message to the ASA (ALT) family, O’Neill said he is working with the Army secretary and DoD acquisition chief Ashton Carter to ensure the service’s acquisition side continues to operate without interruption.

“It has been my great privilege to lead the Army Materiel Enterprise, a hard working team dedicated to the success of our Soldiers at war and in operations throughout the world,” O’Neill wrote. “I have witnessed firsthand the difference we make in providing the American Soldier, our most important customer with world-class weapon systems and equipment. I am grateful for the many opportunities I have been given during my career and especially in my current position. I have enjoyed my time here, and I wish you every success in the future.”

O’Neill took over the job March 4, 2010 after nomination by President Barack Obama and Senate confirmation.

Before leading Army acquisition, O’Neill was chairman of the board on Army Science and Technology for the National Academies and the National Research Council. From 2000-2006, he was vice president and chief technical Officer of Lockheed Martin [LMT] and from 1996 to 2000 served as vice president for Operations and Best Practices in the Space and Strategic Missiles Division at the company. A veteran of 34 years of active military service, O’Neill retired as a lieutenant general, leading the Ballistic Missile Defense Organization, the predecessor of the Missile Defense Agency in his final assignment.