The Mostly OM is an annual international workshop sponsored by the School of Economics and Management, and the Research Center for Contemporary Management, of Tsinghua University, focusing on the state-of-the-art research in Operations Management (OM), broadly defined. The Mostly OM aims to provide a forum for researchers, from China and overseas alike, to foster interaction and exchange ideas, learn from each other new methodologies and applications, and explore opportunities for collaboration. Each workshop will feature several tutorials that provide in-depth coverage on some of the latest trends and developments in OM research. These will be complemented by a select set of invited presentations from leading researchers worldwide, on topics that are mostly OM but also include other subjects of interest to the community. The Sixth Mostly OM Workshop will be held from June 12 to June 13, 2015, at Tsinghua University, Beijing, China. Looking forward to hearing from you and seeing you in Beijing.