Most countries require you to have a valid license before you will be allowed to drive. Although this may or may not actually be enforced in the country you are visiting, you are still strongly advised not to drive without a valid license, as you could be subject to fines and possible imprisonment if caught, and any insurance policies you may have purchased will not cover you in the event of an accident.

In addition to having your driver's licence, you may need to satisfy age requirements, such as 18 years for driving a regular car or 21 for heavier vehicles or heavy trailers; for heavy vehicles there may be additional requirements.

Most countries allow foreign licenses, especially from neighboring countries and licences that follow international standards; for example Canada and the USA accept each others' licenses, as do the EU countries. Exceptions include China, where a domestic driver's licence is required.

If your domestic driver's licence fulfils the requirements of the international standard, it will be valid at least in countries who have signed it. If not, it is valid if accompanied by an International Driving Permit (IDP) as laid up in the convention. Some countries that have not signed the convention may nevertheless accept your licence accompanied by an IDP. There is also the ISO/IEC 18013, designed to replace the IDP, but it is not widely recognised.

The IDP is issued by an authorised body; usually it can be obtained from the automobile association in your country of residence. There are many resellers on the net, not all of them recognised, see a list of approved organisations. The IDP is valid for a stay of at most a year, and at most for three years from the issuing date. If your country is not part of the convention you may be out of luck.

If your stay in a country is much longer than a typical tourist's visit, you will often have to get a local license. This may involve simply exchanging your foreign license for a local one or going through the full courses and testing as a local who has no license would have to.

The draw bridge warning sign is one of the several signs that remain text-only in the U.S.A. (left), while its equivalents under the Vienna Convention (right) display a symbol of an open draw bridge.

Straight ahead only: U.S.A. (left), Brazil (center) and Vienna (right). The Vienna convention uses a category of mandatory instructions, in most countries round signs with white symbols on blue background (the Brazilian variant is an option).

About half of the world, including most of Europe and Central Asia, and parts of Africa, follows the 1968 Vienna conventions on road traffic and on signs and signals (developed by the UN, based on the European tradition). If you are used to driving in one such country, most signs and rules will be familiar. The signs in these countries are mostly pictograms, which require no knowledge of the language. The meaning of some symbols may still not be self-evident, and additional signs may be textual, such as a parking sign having an addition of "residents only". Those who are not concerned by the main sign should not need to understand the auxiliary signs.

China is not a signatory to the Vienna convention but uses a system that is very similar.

Another important standard is the domestic US one (with state-specific variations), which has influenced much of the world. Australia, Canada and Mexico follow a system in this tradition, which for regulatory signs and warning signs relies more heavily on text in the respective national languages.

South America, South-East Asia, Ireland, Japan and New Zealand use different adaptions and mixtures of both the above traditions.

Main article: Car rental

Renting a car is often more practical than bringing your own, but there are many things to watch out for. Check the small print and make sure to note initial condition of the car, not to be told to pay for earlier damage.

You usually pay per day (although long rentals may be cheaper), so you might want to plan on having a car just certain days.

In many cases the requirements for driving a rental car are higher than for a driver's license in and of itself. For example, there may be a higher age limit or the rental company may require a certain number of years of experience driving. If you have renewed you license recently, it might be wise to keep the old one to prove that you have, in fact, been driving for a longer time.

Check your insurance; not all policies cover international travel and even those that do may not meet the requirements of a destination's regulations. You really do not want to find yourself having to appear in court because of an accident your insurance did not cover, especially when the court may be far from your home or may operate in a foreign language. Nor do you want bills your insurance does not cover, whether auto repair, legal or medical.

Some borders may be no problem to cross with your own car, but many rental contracts forbid driving to certain neighboring countries or even some regions and jurisdictions of the same country. You may also need more documentation than at home, e.g. proving ownership. Often you need a sign showing the nationality of your car. At some borders, you need to change the side of the road that you drive on.

Bringing a vehicle into some countries requires a Carnet de Passages; like the IDP this is usually obtained from the automobile association in your home country.

Road conditions and driving habits vary from country to country and between regions. If you will drive in winter or in mountains, check implications of winter driving. If you may be using unpaved roads or roads in bad condition, check what to expect, and also the fine print of your insurance and rental contracts. In sparsely inhabited areas navigating may involve some challenges and breaking down or losing your way is worse than near people. Have and use a map, and get your GPS working.

Fuel prices vary considerably from one country to the next. While fuel is often cheap in oil-producing countries this is not so straightforward: Norway is a big oil producer with some of the world's highest prices for petrol, while in USA, which has to import much of its consumption, keeping gas prices down is politically important.

Because of different taxation across borders, filling up before crossing or getting over the border before filling up can save you money. Don't gamble with the last liters though.

When renting a car, you might want to know how thirsty your first choice is. In the USA this is measured as miles per gallon, while in most of Europe the measure is litres per 100 km. In the former case you want a big figure (such as 53), in the latter a small one (such as 4.5). Typical fuel efficiency varies between countries, as does what kind of driving is assumed for the measures, and the testing procedure itself (unified across the EU though).

Fuel quality also varies, and what different qualities are called. In some countries you can buy a type that suits your car where it is cheapest, while in others you may want to stick to the most reputable chains.

Diesel is commonly cheaper due to lower taxation in some European countries but it may be rare or unavailable in other countries. You can't drive a gasoline car with diesel or vice versa.

The type of service in fuel stations differs:

• Full service — An attendant operates the pumps, often wipes the windshield, and sometimes checks the vehicle's oil level and tire pressure, then collects payment and perhaps a small tip.
• Minimum service — An attendant operates the pumps. This is often required due to legislation that prohibits customers from operating the pumps.
• Self service — The customer performs all required service. Signs informing the customer of filling procedures and cautions are displayed on each pump. Customers can still enter a store or go to a booth to give payment to a person.
• Unstaffed — Using cardlock (or pay-at-the-pump) system, these are completely unstaffed.

Self-service stations are found in developed countries like the United States and Canada, while full-service stations are commonly found (and are sometimes the only type of fuel station available) in many developing countries. There are a number of places that do not allow self-service at gas stations for regular fuel – station attendants must be the ones to pump gas. These include Brazil, China, Turkey, South Africa, Uruguay, North Korea, a few other developing countries, and the state of New Jersey in the United States,.

Parking can be a hassle, not least in cities. Parking rules differ between countries, and violation can give a hefty fine or having your vehicle towed away.

A parking disc is a clock-like ticket which indicates parking time. It is mandated in many European cities.

In Africa, most transport infrastructure is not developed, and it is hard to get around, even by car, in many places of Africa. Continued political instability and frequent regime changes in Africa will further underfund new road construction in Africa. If you do wish to drive in African countries, North African countries and South Africa do have generally good road networks in urban areas, but in many other countries in Africa, driving can be dangerous due to the poor condition of many road networks.

New road construction has not always kept up with growing traffic, and congestion is a major problem, especially in urban centers. Still, a car is often a good and sometimes the only way to explore more remote areas. Bringing a car might necessitate a number of forms and permits; you will probably need an international driving permit and for some countries a Carnet de Passages for the vehicle. Mainland China requires their own driving licence.

In East Asia (countries like China, Japan, and South Korea), many places have good public transport and rail travel systems, and high-speed rail is often the preferred mode of intercity travel within a country in East Asia, so there is usually no need to drive. Southeast Asian countries (excluding Singapore) have a strong car culture; while public transport is available in large cities, a car is a preferred way to get around elsewhere (only Singapore has an extensive and good public transport system). In South Asia (countries like India and Bangladesh), as well as in West Asia (countries like Israel and Jordan), popular intercity bus systems serve most destinations of interest and buses are preferred a form of public transport there, but in some West Asian countries like United Arab Emirates and Saudi Arabia, strong car culture does occur. In Central Asia, transport infrastructure, such as highways, are underdeveloped, and travelling by car is challenging.

All of Asia is part of Asian Highway Network, the Asian continent counterpart of the European network or the Interstate Highway System. While a number of countries in Central Asia, such as Uzbekistan, are part of European route network, road signs in many Asian countries do not identify E-routes. Some, such as North Korea and Turkey, do not identify AH-routes.

Main article: Driving in Europe

Europe generally has good road networks, although high population density means that there can be a lot of other cars on the road, making driving more difficult, and there are remote areas where roads are in bad condition. Driving in cities is often problematic and there is good public transportation, so a car is usually needed only for the countryside.

In most countries the signs and rules follow the 1968 Vienna conventions.

• Driving in Denmark
• Driving in Finland
• Driving in France
• Driving in Germany
• Driving in Iceland
• Driving in Italy
• Driving in Norway
• Driving in Poland
• Driving in Portugal
• Driving in Russia
• Driving in Spain
• Driving in Sweden
• Driving in Switzerland
• Driving in the United Kingdom

In Oceania, especially in Australia and New Zealand, road networks are in good condition. Most adults in Oceania drive to get around their respective cities.

Although Germany is the birthplace of the automobile and its inventor, Karl Benz, the United States is the first country to embrace consumerist car culture. With American influence, car culture spread north to Canada, and south into Mexico and Central America, and as a result, most adults in North America (generally in Canada, United States, Mexico) drive to get around their respective cities. If you do not want to drive, popular intercity bus systems (like Greyhound for example) serve most destinations of interest (but be careful that there is little security), as much of the rail network in North America is generally built for freight (although passenger rail travel is experiencing a revival in North America starting in the 2020s).

The United States is also the birthplace of MUTCD, which has influenced road signage across the Western Hemisphere, including North America.

Popular intercity bus systems serve most destinations of interest, but by car you can reach also places that aren't served (or are badly served) by public transport. Expect busy traffic in large cities and extremely variable road conditions in the countryside.

For traffic rules and signs, most countries in South America have adopted some mixture of the US standards and the UN ones (the 1968 Vienna conventions). To what degree they follow each varies.

If you are unused to bikers, watch out! Rules differ by country, but there are several dangerous situations. The main thing is that you should behave predictably and look for them – if you only look for cars before turning or opening a door, you may kill a fast cyclist you didn't notice.

In city traffic, cyclists may well be faster than you. Often they use the right edge of the road or lane, and especially when you slow down to turn or park, they may close in in no time. Make sure to use your blinkers and to specifically look for them. Never forget one you see, thinking they are too far to matter. Always check for cyclists before opening a door.

In some countries cyclists may be allowed to use the left side of the road (or cycle in the opposite direction on unidirectional roads) and thus surprise you. Sometimes they do even if not allowed to. An especially hazardous situation is when there is a bidirectional cycleway on your side of a street you are going to cross. Remember to look also for those to your right on the cycleway. (And the other way around where you drive to the left.)

In countries were cycling is common, you often have several categories: old or less fit people cycling at jogging speed and those racing faster than city car traffic. Some may follow rules precisely, and trust you to do the same, while others may be totally ignorant. Don't trust your first impression of biking in the country.

Fatigue can be fatal. If you are driving for many hours in a row, take a break to get some fresh air, stretch your legs and most importantly switch off from driving for a bit. If you drive into the night or early morning, not only is it more dangerous due to it being dark but there is every chance you can start to nod off. If you leave early in the morning or don't have a lot of sleep before heading out, you should be aware that you may not be at your sharpest. Caffeine can only help so much: the only real cure for fatigue is sleep.

Most people use their phones to navigate. Do not let your phone distract you. A dashboard-mounted phone holder will help minimize hazards arising from navigating or talking on the phone. Talking over the phone, taking a look at the map or changing a setting still distracts you; pull over for anything that requires looking away from the road for more than half a second, and if you use those half-seconds often, you'd better take a break or find a human navigator.

Sometimes talking helps with fatigue or is otherwise necessary. Make sure you can ignore the phone at any moment to concentrate on driving – if your talking companion doesn't understand that need, don't talk to them while driving. Likewise, small talk keeps you awake, while anything that upsets you or requires serious thinking is away from your concentration.

In some areas, automotive vandalism or theft can be quite common. To mitigate risk, keep your doors locked when you are away from the car or when the car is in motion, and the windows up when possible. Keep valuables on your person, or out of view in the trunk or glovebox if that is not practical. In some areas, criminals may try to siphon off gas from your car, install credit card skimmers at gas station pumps, or offer to "protect" your parked car for a fee (and damage your car if you park there without paying them). Some more modern cars are equipped with anti theft systems that can send an alert to your phone if it detects unusual activity.

If you are going to drive in the Arctic, in winter in temperate climates or in mountains (including mountain passes), you should acquaint yourself with advice for winter driving. The roads will be slippery, sight may be reduced (snow can cause "whiteouts" where you hardly see ten metres) and getting stuck will make you have to cope with cold weather.

Dense fog may actually be the deadliest weather phenomenon you encounter, as it drastically reduces visibility and thus causes traffic accidents. Sometimes there is fog only in valleys or by bodies of water; when driving downhill visibility can be abruptly reduced unless you are alert.

Flooding can trap you. Driving on a road covered with water is dangerous as judging the depth and the condition of the road (which may have been damaged) is difficult. Water can destroy the engine by abruptly cooling parts of it, and if deep enough (about 60 cm, two feet) even sweep away the car.

• Check-up. Before driving through mountainous terrain, especially after the cold winter months, your car may need extra attention. Make sure that the vehicle's brake and transmission fluids are filled.
• Warn friends or relatives where and for long you are leaving. Tell a hard deadline when they should initiate a search. Take into account that you may not have phone coverage in some areas. Also tell people that could get nervous if they cannot reach you.
• Maps and route. In remote areas small roads may not be mapped completely or accurately. Or the opposite: an unpassable road in a bad condition might be mapped as good quality asphalt tertiary road. To avoid a wrong turn, plot out your trip on an old-fashioned paper map before you depart.
• Fuel. Many people don't realize that climbing steep grades requires much more fuel than a typical drive. Also, fuel stations and cell coverage can be sparse.
• Use brakes sparingly.
• Downshift before extreme downgrades, to use the engine for braking.
• Watch your temperature gauge.
• Stay alert and on your side of the road.

Motion sickness is most likely to affect children and young people. Vulnerable individuals should get medication, or at least keep eyesight on the outdoor environment.