Visas are not required by nationals from Armenia, Austria, Azerbaijan, Belarus, Belgium, Bulgaria, Canada, Cyprus, Czech, Denmark, Estonia, Finland, France, Georgia, Germany, Great Britain, Greece, Hungary, Iceland, Ireland, Italy, Japan, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Russia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Tajikistan, Ukraine, USA and Uzbekistan
Everyone else will need to obtain an invitation and head to an embassy.
Visa Information for Moldova
Moldova Embassies
Foreign embassies in Moldova
Visas for the Republic of Transdnister (Trans-Dniester) are not required when entering from Moldova, all you need is a current passport.