Background: Connective tissue nevi (CTN) are circumscribed hamartomas of the skin in which there is an abnormal mixture of normal components of the dermis that may be sporadic or associated with syndromes such as Buschke-Ollendorff, tuberous sclerosis, and Proteus. Objective: We sought to specify the clinical and histologic features of CTN in childhood and to propose a diagnostic approach and updated classification. Methods: This was a retrospective study in a tertiary pediatric outpatient population, accessing clinical and histopathological records. Results: We classified 114 cases of CTN from 1980 to 2008. Limitations: The majority of cases were confirmed by histopathological examination. Therefore, our series excludes many CTN that were not biopsied. In addition, follow-up was variable. Conclusion: Our series demonstrates the usefulness of a modified classification for CTN. Biopsy should be done when clinical diagnosis is uncertain, or in multiple lesions. When biopsy is performed it should include normal-appearing skin for comparison and, in Buschke-Ollendorff syndrome, limited anterior-posterior x-rays of the hands, wrists, feet, ankles, knees, and pelvis instead of a full skeletal survey.