Three cases of deep soft-tissue infections caused by Streptococcus pneumoniae are presented. All patients were previously healthy adults. The first case was a man with a protracted illness in whom pelvic and inguinal abscesses developed at the site of a scar from a traumatic injury several years earlier. The second patient, a woman, had mastitis with systemic symptoms. The third patient was a woman who developed a gluteal abscess after an intramuscular injection of a contraceptive. Cellulitis and deep soft-tissue infections caused by Streptococcus pneumoniae are uncommon, but may occur even in immunocompetent adults.