Source: OECD.

Loss of Life per 10,000 Vehicles, OECD Countries, 1993-1995

World wide, more than 500,000 people are killed and several million are injured each year as a result of transport accidents. There is a 1 in 20,000 chance of being killed in a road traffic accident; representing a tenfold likelihood over air traffic fatalities. Every year, there are 50 million road accidents of which 12% result in bodily injury. Road accidents are complex phenomenon where several variables often interact (alcohol, network quality, speed, meteorological conditions, driver behavior, etc.). It is possible, however, to regroup these variables in three major factors: the vehicle, the user, and the environment (infrastructure and traffic). Road safety is an important social stakeholder. Insecurity is a major (and often disregarded) problem. It seems that in most developed nations, the number of people killed per annum is on the decline. Therefore, progress occurs in matters of health (emergency) and technology (roads, vehicles). However, the risk itself is not contained because mobility has increased.

Drivers generally tend to underestimate the probability of accidents or to overestimate their ability to avoid them. Risk perception becomes a compromise between regulation, psychological tendencies and the social values of individuals. Risks cannot exist without a "social construction" which stipulates that some danger is privileged while others are simply ignored. Other variables must be considered such as those which diminish awareness and reflexes; ageing, fatigue, medicine, drugs, alcohol, etc. Speed is also a factor of road accident risk. The greater the speed, the greater the driving difficulties and the corresponding risk to the driver's (and other users') safety. 

Accidents are events which occur at a precise moment in time and a precise area in space. They are becoming normative occurrences of daily life with a growing acceptance from society. Human factors can be attributed to no less than 85% of accidents. It would thus be impossible to transform the road into a completely safe transport medium.

Given the complexity of the issue with regards to the people, location and causes implied in accidents, there cannot exist a single all-encompassing approach. Regulation of vehicles, infrastructure, and behavior (education, prevention, awareness, and repression) is commonly perceived a a tool to achieve such a purpose. Road safety acts can influence the consequences of accidents. For example, speed limits, better public transit management, restricted time periods for automobile access in specific neighborhoods and lanes are methods assumed to have an impact. It is important to remember that the amount of accidents is proportional with mobility. It is impossible to reduce one without directly impacting the other.