Odd-Helge Fjeldstad from the Chr. Michelsen Institute, a partner in the TaxCapDev-network led by NUPI, has written a chapter in the World Bank's recently published Global Report on Anti-Corruption together with Gael Raballand. 

Here they argue that addressing the root causes of corruption goes beyond legal reforms, code of ethics or IT system upgrades. Many important initiatives have been taken in these regards but the results have often been disappointing in developing economy contexts. 

Fjeldstad and Raballand argue that a legal framework, simplification of processes and imports policies and automation must be supplemented with other comprehensive approaches that address the root causes of corruption. 

The reason is that corruption is deeply embedded in the social norms and expectations of social and political life. Such norms provide the unwritten rules of behaviour that can be difficult obstacles in the fight against corruption. 

Though corruption remains a problem for many countries, strong political will, local buy-in and improved awareness can help them get on the right path. 

You can read more about this in Fjeldstad and Raballand's World Bank blogpost
and in the World Bank report Enhancing Government Effectiveness and Transparency: The Fight Against Corruption.