On behalf of the Swedish Institute for Transport and Communications Analysis (SIKA), an estimate has been made of the effect on traffic safety of total compliance with the current speed limits, seat belt use and driver sobriety. A very high degree of observance of the three measures would mean that the number killed in traffic would be reduced by almost 50%. What is of interest is that observance is not randomly distributed among the three measures. Both the drivers who adjust their driving to the three measures, and those who simultaneously contravene two or all three of the measures, are overrepresented in traffic.