Antigenic stimulation of a local inductive site causes the appearance of antibody-producing cells in many parts of the effector sites. Some linking between the inductive site and the effector site has been shown in regards to the efficiency of antibody induction. Several years ago, we showed that palatine tonsils served as an inductive site for mucosal immunity especially for salivary glands. We reexamine the close linking between palatine tonsils and salivary glands, and discuss the role of palatine tonsils in relation to microorganisms in the respiratory and digestive tracts.