The A.T. Kearney consultancy company published its fifth annual rankings on its web site.
This year, Croatia went up seven places on the rankings, at the top of which is Singapore.
The index measures 12 variables categorised in four groups: economic integration, personal contact, technological connectivity and political engagement.
The 62 countries covered by the survey account for 96 percent of the global Gross Domestic Product and have 85 percent of the world population.
Croatia has gone up seven places mostly thanks to a 50-percent rise in foreign direct investments.
"Croatia jumped seven spots, while Romania and Ukraine moved up four notches apiece. Trade flows for each of these countries were up between 26 percent and 36 percent, and FDI (foreign direct investments) increased more than 50 percent for Croatia," reads the report.
According to the report, in 2003, "the wave of investment moved on to lower-cost countries that may be included in the next (EU) membership round, including Croatia, Romania and Ukraine".
Of other central and eastern European countries, only the Czech Republic is in front of Croatia and was ranked 15th. Slovenia, for instance, was ranked 20th.