The aim of the present study was to investigate the aetiology and antibiotic-resistance patterns of community-acquired lower respiratory tract infection (LRTI) in 1999 and compare it with data from 1995 and 1988. A prospective observational study of LRTI in hospitalized children at KK Women's & Children's Hospital, Singapore, was undertaken. A positive isolate was found in 58% of patients (671/1158), comprising viruses (n = 477, 41.2%), non-type B Haemophilus influenzae (n = 101, 8.7%), Streptococcus pneumoniae (n = 66, 5.7%), Mycoplasma pneumoniae (n = 92, 8%), Moraxella catarrhalis (n = 19, 1.6%) and other bacteria (n = 19, 1.6%). Mixed virus-bacteria (n = 104, 9%) infections were comprised mostly of virus-H. influenzae combinations. In 1999, S. pneumoniae resistance rates were penicillin 44.6% (17%, 1995), amoxycillin 3% (18%, 1995; MIC 0.5-2 microg/mL reclassified as susceptible in 1999), erythromycin 55% (30%, 1995), trimethoprim-sulfamethoxazole (TMP/SMX) 60% (23%, 1995). H. influenzaeresistance rates were amoxycillin 26.7% (38%, 1995), erythromycin 99% (37%, 1995), TMP/SMX 98% (37%, 1995). There were 15 cases of empyema of which seven were proven S. pneumoniae and there was one pneumococcal death (0.08%). Pneumococcal pneumonia needs to be treated aggressively due to its high morbidity. Amoxycillin still remains useful for treating pneumococcus despite an increasing resistance to penicillin, erythromycin and TMP/SMX. Judicious use of antibiotics is needed to curb the increasing rate of antibiotic-resistance.