Providers' periodontal diagnostic and treatment behaviors were assessed in 34 practices in two North Carolina counties. Regularly attending patients had a low prevalence of gingival pocketing on index teeth, moderate attachment loss, and fairly prevalent bleeding and calculus. Treatment frequency and patient knowledge were generally adequate, but the notation of periodontal status in the patient record was insufficient. A continuing education intervention resulted in substantial and significant improvement in notation rates. Changes in rates with which services were provided, and changes in patient periodontal status were smaller and mixed. The study shows that continuing education can be effective in helping some but not all providers adopt needed, appropriate behaviors.