Taiwan has one of the highest levels of antibiotic-resistant pneumococcus in the world. Pneumococcal isolates not susceptible to penicillin first appeared in Taiwan in 1986; in 1995 an increase in the prevalence of nonsusceptibility to penicillins, extended-spectrum cephalosporins, trimethoprim-sulfamethoxazole, and macrolides as well as multidrug resistance began to be recognized. With the persistence of antibiotic selective pressure, resistance in some antibiotics reached a high plateau (beta-lactam antibiotics) or continued to increase (macrolides), while novel resistance (fluoroquinolones) emerged in the last 3 years. Widespread distribution of some novel resistant 23F and 19F clones (and the international epidemic of 23F clones) contributes further to the rapid increase of resistance. Because Streptococcus pneumoniae is a major pathogen that causes community-acquired lower respiratory tract infections and meningitis in adults and children, antibiotic-resistance in this organism is a serious problem.