Every nationality needs a valid passport to enter the Dominican Republic . Most travelers don’t need visas, just a tourist card. Check www.godominicanrepublic.com  for a complete list of countries and requirements.
Tourist cards cost US$10 and are valid for up to 30 days. They can be purchased upon arrival. To stay longer than 30 days, you will need to pay about US$5 for each month you have overstayed.
No vaccinations are required for entry into the Dominican Republic, but some are recommended for longer stays: hepatitis A, hepatitis B, tetanus-diphtheria, typhoid, chickenpox, and rabies.
Many tourists take advantage of discounted packages available online that include airfare, all-inclusive hotel, and transportation. Crave a bit more independence? Try booking online for flights only, with sites like www.expedia.com  or www.orbitz.com .
Once on the ground, taxis are easy to find at all airports. Agree on price before getting into the car. Santo Domingo ’s public taxi system is the público. These cheap public taxis have set routes and act as buses picking up other riders along their routes. Motoconchos are small moto-taxis. Although cost-effective, they can be dangerous and are recommended only for the adventurous.
Although car rental gives you freedom from the schedules of public transportation, fees and fuel costs run high, as do auto incidents.
The two major bus companies, Caribe Tours and Metro, have comfortable buses shuttling between major cities. Getting to smaller towns is done via the even cheaper guagua system. Guaguas are often crowded, and tourists can be overcharged.