This research was conducted to study incidence, distribution, type, causes, severity and circumstances of injuries among people living in squatter settlements in Karachi, Pakistan. Trained interviewers sought a 2 weeks recall for minor injuries for which no health care was sought, 2 months recall for major injuries for which a health provider was consulted and 1 year recall for hospitalization, disability and death from every third household in five squatter settlements in Karachi between May and August 1995. For understanding the injury circumstances 250 in-depth interviews of the injured or the close relatives were also conducted. Among 1182 households, having 9891 residents, 84 minor, 42 major injury episodes, 7 hospitalizations, 0.6 permanent disabilities and 0.3 deaths per 1000 person years were reported. Including all injury episodes, the common types of injury were cutting or piercing (n = 532), falls (n = 382) and burns (n = 235) estimating to 54, 38 and 23 injury episodes per 1000 person years. Injury mainly resulted from a piece of glass (n = 367), falling from height (n = 98) and knife (n = 97) estimating to 37, 10 and 10 injury episodes per 1000 person years, respectively. Fall (n = 32, 3.2/1000 person years) was the major reason for hospitalizations and all permanent disabilities resulted from closed injuries. Medically trained providers were mostly contacted (n = 339, 34/1000 person years), but traditional healers were preferred in bone injury. Injuries are a major cause of morbidity and mortality in Pakistan and the national health and development agenda should include assessment and prevention of injuries.