Skip to main content
School of Law

Vasiliki Koukoulioti


PhD Student



Thesis title

The Benefit Principle Revisited - Avoiding the Repercussions of Digitalization on the Tax Base Sustainability (working title).


Summary of research

Digitalization challenges the sustainability of the current international tax system, which is founded on the principles of residence and source. The notion of source fails as a doctrinal rule to have a normative content in the context of the modern digitalized economy. The reconceptualization of the source principle presupposes revisiting its main justification, the benefit principle, which has functioned both as a justification for taxation and as a tool to allocate taxing rights internationally. Nevertheless, the possibility to conduct business activities without any (significant) physical presence, and the consequent disconnection between sources of income and benefits provided, has challenged the normative foundation of the benefit principle.

The present research intends to explore possible responses to the disputed validity of the benefit principle in the current reality of technological advancements. For this reason, the “reverse benefit approach” is proposed, based on which the determinant for tax allocation purposes should be the benefits received, instead of those provided, by the state. As a consequence, the division of the international tax pie among states is performed depending on the level of economic growth of the various jurisdictions involved in the generation of income attributing a bigger share to jurisdictions that benefit the most from investments in terms of economic growth, i.e. less economically developed states. In that way, this proposal intends to restore the wealth redistribution function of taxation and underline the role of taxes in supporting sustainable development.


I am a PhD Researcher at the Centre for Commercial Law Studies, Queen Mary University of London and have been awarded the Microsoft-funded Cloud Legal Project CCLS Studentship for the purpose of pursuing my PhD. My research focuses on the tax law implications from a corporate income tax point of view of the digitalization of the economy, in general, having a tax policy approach. I am a qualified Greek attorney-at-law and prior to joining the Cloud Legal Project I worked as a tax lawyer for tax law firms in Athens, Greece and as a senior tax consultant at PwC Athens, Greece for five years providing tax advice and tax litigation services to multinational enterprises and high net worth individuals. I have obtained an LL.M. in Tax Law with Merit from QMUL, in 2012 and an Advanced Diploma in International Taxation (ADIT) modular certificate from the Chartered Institute of Taxation (CIOT), London, in 2014.


Back to top