Visitors from all countries require a passport and citizens from most countries including Canada, the United States, and the United Kingdom (with some exceptions including Isle of Man and Guernsey) need an Ordinary Visa/Single-Entry Visa ($50 USD as of this writing – confirm price through link) to enter Tanzania. These visas can normally be purchased online. However, the Goverment of Tanzania recommends that you purchase directly from official websites — there are many visa services online that are not officially recognized by the Tanzanian government. Other documentation may be required including proof of a return flight. Find more information including official Visa Guidelines here.