The aim of this study was to investigate the relationship between trip-focused organizational safety climate, and driver behaviours, (i.e., errors, violations and positive driver behaviours) in professional driving. A total of 219 male professional drivers participated in the study. The participants were asked to fill out the Driver Behaviour Questionnaire together with the Positive Driver Behaviours Scale; Trip-focused Organizational Safety Climate Scale (TOSCS); and a demographic information form. Factor analysis of the TOSCS, which has been used for the first time in the present study, resulted in a two-factor solution. The factors were named as 'Trip Safety Monitoring and Control' (TSMC) and Tacit Agreement to Trip Safety' (TATS). In order to test the main and interaction effects of organizational safety climate on driver behaviours of professional drivers, Analyses of Covariance were conducted after controlling for the statistical effects of age and annual mileage of the drivers, and the type of the organizations for which they are working. According to the results, professional drivers with low scores of TATS reported higher frequencies of errors and violations as compared to the drivers with high scores of TATS. Interaction effect between TSMC and TATS dimensions was found on the frequencies of positive driver behaviours. Such that, the highest frequencies of positive driver behaviours were reported when both TSMC and TATS scores were high, while the lowest frequencies of positive driver behaviours were reported when TSMC scores were low but TATS scores were high. In the present study, driver behaviours of professional drivers have been studied for the first time on the basis of the trip-focused aspect of organizational safety climate. This study is also the first one evidencing the relationship between organizational safety climate and positive driver behaviours. (C) 2014 Elsevier Ltd. All rights reserved.