Various tissue thickness compensators (19100, 19200, 19300, 19400, 19500, 10601, 19700, 19800, 19900, 20000, 20100, 20200, 20300, 20500, 20600, 20700, 20800, 20900) are disclosed for deployment between a stapler head of a surgical circular stapler and an anvil attached thereto to accommodate variances in tissue thickness during stapling. Some tissue thickness compensator arrangements include means and configurations for deploying healing agents for enhancing the healing process. The tissue thickness ompnsators (19100) are attached to the anvil by attachment members (19112, 19130, 19070).