['To investigate the methods used by patients diagnosed with a sexually transmissible infection (STI) to inform their partners during contact tracing.', 'At a large Australian sexual health clinic between March and May 2010, we undertook a retrospective, cross sectional analysis of the methods used by patients diagnosed with a bacterial STI to inform their partners.', 'Of the 172 index patients contacted 1\u2005week after treatment, 163 (95%) chose patient referral, 3 (2%) provider referral and 6 (3%) could not contact any partners. Index patients nominated 1010 sexual partners of whom 494 (49%) were reported as contactable. A total of 447/494 (91%) of these partners were successfully informed; telephone (37%) and face to face (22%) were the most used methods. After multivariate analysis, predictors of using face to face contact methods were age <30\u2005years (AOR: 2.8; 95% CI 1.4 to 5.7), fewer than 2 sexual partners (AOR 3.6; 95% CI 1.7 to 7.6) and speaking a language other than English (adjusted OR (AOR) 3.1; 95% CI 1.3 to 7.2). The single predictor of using interactive contact methods (face to face+telephone) was reporting fewer than 2 sexual partners (AOR 2.7; 95% CI 1.3 to 5.5). People diagnosed with syphilis were significantly less likely to use an interactive contact tracing method (AOR 0.24; 95% CI 0.09 to 0.67).'] Do a cross sectional study of how people diagnosed with a bacterial sexually transmitted infection inform their partners?