Osteomyelitis, or bone infection, affects all age groups and develops from various sources including haematogenously from distant infection foci, from external sources such as post-operative or post-traumatic wound infections and from adjoining soft tissue infections. Staphylococcus aureus, Streptococcus pyogenes and Haemophilus influenzae are the most common pathogens of haematogenous osteomyelitis. Aerobic and facultative gram-negative bacteria have emerged as significant pathogens in some types of osteomyelitis while anaerobic bacteria are increasingly recognized as potential pathogens in non-haematogenous osteomyelitis. The emergence of antibiotic resistance is of increasing concern, although improvements in radiologic imaging, antibiotic treatment and heightened awareness have led to earlier detection such that long-term sequelae and morbidity are now primarily due to delays in diagnosis and inadequate treatment.