For people with a recognised Master 's degree, ACTA offers the possibility of earning a doctorate, or the Anglo-Saxon PhD degree. The process of PhD normally takes four years or more and consists of conducting independent research and writing a dissertation.

A Master’s degree is the prerequisite to be eligible to work on a PhD-thesis. The project takes at least four years and consists of independent research, supervised by a professor ('promotor'), who has consented to lend his or her assistance. The PhD student ('promovendus') is not a student, nor is he or she registered as such at the university. The promovendus is required to incorporate the findings of his or her research in a doctoral dissertation ('proefschrift'), and to defend it in a public sitting of the university's Council of Deans.

Some PhD students are employed by the university as trainee research assistants ('Assistent in Opleiding', AIO) or as a trainee researcher ('Onderzoeker in Opleiding', OIO). The PhD student may also be employed elsewhere or carry out research in his or her own time. However, in order to work in the Netherlands, foreign PhD students must have a residence permit specifically for this purpose, which may be difficult to obtain for non-European Union (EU) nationals.