IN RECENT YEARS, evidence has evolved that suggests a relationship between fibrinolytic phenomenon and various inflammatory diseases. Plasmin activity and the response of the fibrinogen and fibrin degradation products latex test (FDPL test) in gingival fluid, along with plasminogen activator activity in gingival tissue were assessed. Samples were taken from periodontally involved persons and compared with healthy individuals. The following conclusions could be drawn: (1) The fluid from inflamed gingival crevices possessed more plasmin activity than that from clinically healthy crevices. The reaction of the FDPL test was stronger in the former. (2) Plasminogen activator activity in gingival tissue showed no significant difference between periodontally involved and healthy subjects.