Physicians have long expressed dissatisfaction with the time they and their staffs spend interacting with health plans. However, little information exists about the extent of these interactions.We conducted a national survey on this subject of physicians and practice administrators. Physicians reported spending three hours weekly interacting with plans; nursing and clerical staff spent much larger amounts of time. When time is converted to dollars, we estimate that the national time cost to practices of interactions with plans is at least $23 billion to $31 billion each year. [Health Affairs 28, no. 4 (2009): w533– w543 (published online 14 May 2009; 10.1377/hlthaff.28.4.w533)]