REUTERS/Srdjan Zivulovic
As the WEF's report puts it:
"Sound legal and competition institutions support efficient resource allocation and equal opportunity by preventing corruption, unduly high barriers to entry, and concentration of rents due to regulatory capture.
"Investment climate rules, incentives, and institutional capacity are important for enabling investors to capitalize on the level playing field created by robust legal and competition frameworks."
A big part of that is ensuring that corruption is kept to a minimum within businesses. To that end, one of the things the WEF ranks is how well corruption is fought and the ethics of political and business environments.
You can see the countries doing the best below (scores are given out of seven, with seven being the highest):