Risky road user behaviour is behaviour that adversely affects road safety, such as driving under the influence of alcohol, drugs or medicines, speeding, inappropriate speed, distracted or fatigued driving, red light negation, and failure to use or misuse means of protection (motorcycle or moped helmet, seatbelt). Younger road users more often display risky behaviour than older road users, and men more often than women.

A safe infrastructure is of vital importance to pedestrians and cyclists. In 2010-2019, 40% of the number of road deaths were pedestrians or cyclists. In 2018, they even made up 69% of the number of seriously injured road users.

The mobile phone is symbolic of ‘distraction in traffic’. But apart from mobile phone calls, texting, or listening to music, many drivers, cyclists and pedestrians are occupied with all sorts of other activities that may distract them. Examples are: operating the navigation system, eating, drinking, talking to passengers or daydreaming.

Driving under the influence of drugs or impairing medicines reduces fitness to drive[i] and increases crash risk. Drugs have a numbing, stimulating or mind-altering effect on the brain, or a combination of these effects, which impair traffic task performance. For drug use in traffic, we (unfortunately) have to rely on research dating back to 2011.

Driver fatigue is estimated to be a (contributing) factor in 15 to 20% of crashes, but estimates in individual studies vary widely. Drivers who are tired are less attentive and react less quickly and less adequately than drivers who are not tired. They also get irritated and frustrated more easily.

Sustainable Road Safety implies that the traffic environment is designed to rule out serious crashes and to mitigate the severity of the crashes that do happen. The human dimension is the primary focus: man who is vulnerable, makes mistakes and does not abide by the rules. The road environment, vehicles and technology are to offer support and protection in order to make the safety of the traffic system as little dependent on individual actions as possible. Traffic professionals and central government ensure that these conditions are always met and that imperfections are corrected.

Visual information is of the utmost importance to road users. In darkness, both public lighting and vehicle lighting help road users take stock of the traffic situation and help them to be seen by others. Installing public lighting leads to a 50% reduction in the number of nighttime injury crashes. Disavantages of public lighting are, among other things, the risk of collisons with lamp posts, light pollution and the costs of material, maintenance and energy consumption. The road safety effects of a reduction in illuminance level on motorways vary according to the traffic situation.

A 30 km/h zone is also known as a ‘zone 30’ or a 'residential area'. The zone is mostly situated within an urban area and consists of connected access roads with a 30 km/h speed limit. The areas have a residential function where slow traffic and motorized traffic mix. For this reason speeds must be low (30 km/h maximum). For example, infrastructural measures at both road sections and intersections (think of humps, plateaus and road narrowings) can be used to realize such a low speed.