Vertical Integration and Market Structure
---- Acknowledgements -----
This paper was prepared for the Handbook of Organizational Economics. We thank the editors, Robert Gibbons and John Roberts, for helpful comments and discussions, and the Ewing Marian Kauffman Foundation (Bresnahan) and the National Science Foundation (Levin) for their support. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.