The purpose of the study was to identify factors that affect the incidence of deep wound infection after hip fracture surgery. Data from a hip fracture database of 7057 consecutively treated patients at a single centre was used to determine the relationship between deep wound sepsis and a number of factors. Fisher's exact test and the unpaired T test were used. All patients were initially followed up in a specialist clinic. In addition a phone call assessment was made at one year from injury to check that no later wound healing complications had occurred. There were 50 cases of deep infection (rate of 0.7%). There was no significant difference in the rate of deep sepsis with regards to the age, sex, pre-operative residential status, mobility or mental test score of the patient. Specialist hip surgeons and Consultants have a lower infection rate compared with surgeons below Consultant grade, p=0.01. The mean length of anaesthesia was longer in the sepsis group (76minutes) compared to the no sepsis group (65minutes), this was significant, p=0.01. The patient's ASA grade and fracture type were not significant factors. The rate of infection in intracapsular fractures treated by hemiarthroplasty was significantly greater than those that had internal fixation, p=0.001. The rate of infection in extracapsular fractures fixed with an extra-medullary device was significantly greater than those fixed with an intra-medullary device, p=0.021. The presence of an infected ulcer on the same leg as the fracture was not associated with a higher rate of deep infection. In conclusion we have found that the experience (seniority) of the surgeon, the length of anaesthesia and the type of fixation used are all significant factors in the development of deep sepsis. These are all potentially modifiable risk factors and should be considered in the treatment of hip fracture patients.