By law, all visitors to Canada require a temporary resident visa, except citizens of countries that were granted visitor visa exemption.
Just recently, Citizenship, Immigration and Multiculturalism Minister Jason Kenney announced that visitors from Croatia will no longer be required to obtain a temporary resident visa.
The Government of Canada conducted a comprehensive country review of Croatia, including a technical visit in December 2008. Visa policy decisions are based on a country-by-country assessment of a number of criteria such as socio-economic profile, immigration issues, travel documents, safety and security issues, border management, human rights, and bilateral relations.
“Removing the visa requirement will facilitate travel for Croatian citizens to Canada and will help improve ties between our two countries” said Minister Kenney.[Source]
For the updated list of countries with visitor visa exemption, click here.