The objective of the PhD thesis is the analysis of the effect of road, traffic and driver risk factors on driver behaviour and accident probability at unexpected incidents, with particular focus on distracted driving. For this purpose, a large driving simulator experiment took place in which 95 participants were asked to drive under different types of distraction (no distraction, conversation with passenger, cell phone use) in different road (urban/rural) and traffic conditions (high/low). Then, within the framework of an advanced statistical methodology, latent analysis through a sequence of four Structural Equation Models allowed to go well beyond the piecemeal analyses of driving performance measures to a sound combined analysis of the interrelationship between risk factors, driving performance, driver error and accident probability at unexpected incidents. Results indicate that more likely to commit driving errors are young or old female drivers at urban areas while more likely to be involved in an accident at an unexpected incident are female drivers in low traffic conditions while talking on the cell phone.