This paper analyzes changes in concentration levels in the U.S. Advertising and Marketing Services (A&MS) industry using publicly released data that have been largely ignored in past discussions of the industrial organization of this industry, namely those available from the U.S. Census Bureau's...

We investigate inter-industry variation in the relative incidence of advertisers' utilization of in-house rather than independent advertising agencies. To account for this variability, we develop a set of hypotheses drawing on two perspectives that figure prominently in the literature on...