PhD in Sustainability Science

A three-year programme with an innovative approach to sustainability issues and a global change perspective.

Application Deadline
3 Mar 2024
Program Level
Programme Location
Tokyo, Japan
Program Start Date
September 2024
Program Brochure 

Applications for September 2024 entry are now closed. 

The Doctor of Philosophy in Sustainability Science Programme is a three-year programme that takes an innovative approach to sustainability, seeking to promote a better understanding of the issues by incorporating global change perspectives.

This programme will equip graduates with comprehensive, multidisciplinary knowledge of sustainability problems, and deepen their understanding of the role of environmental sustainability in addressing current issues related to global change, specifically those related to climate change and biodiversity. Students undertake problem-oriented research by playing an active role in UNU-IAS research projects, and acquire the quantitative and qualitative analytical skills necessary to understand the underlying principles of various systems involved in sustainability issues and debates.

Students can select courses from those offered by UNU-IAS, while also enjoying the opportunity to take courses at other leading universities in Japan such as the University of Tokyo, Sophia University, and International Christian University.

Programme Structure & Language

The programme is offered on a full-time basis only. The academic year starts in September. The standard period to complete the degree requirements is 36 months or six academic semesters, excluding time spent on study leave of absence from the university. By July of their third-year students are expected to complete all of the course requirements, obtaining at least 14 credits and completing a doctoral dissertation.

The language of instruction is English. [Top]

Admission Requirements

Applicants for the PhD in Sustainability Science are required to have met the following requirements by the application deadline in order to be considered:

1. A completed master’s degree (or equivalent) from a recognized university or institution of higher education in a field related to sustainability and a minimum of two years of professional field experience related to UNU-IAS research themes which was acquired after obtaining a university degree (full time equivalent);


Two completed master’s degrees, at least one of which must be in a discipline related to sustainability studies (those who expect to receive a second master’s degree before the entrance period of September 2024 may also apply);

2. A GPA of 2.8 or above on a 4.0 scale (equivalent to 70% on a 100 % scale) for at least one of the master’s degrees earned; and

3. English language proficiency.

The minimum score requirements for English language qualifications required by UNU-IAS are:

  • 600 on TOEFL – Paper-Based Testing (PBT) OR
  • 100 on TOEFL – Internet-Based Testing (IBT) OR
  • 7.0 on IELTS – Academic format

* Please note that TOEFL and ILTS test scores are valid for two years. Invalid test scores will not be accepted. UNU-IAS requires original TOEFL/IELTS score reports (no photocopies accepted).

  • TOEFL: Please order an official score report using the institution code 6991. For more information on TOEFL, please visit
  • IELTS: Please request that an official report be sent directly to UNU-IAS. For more information on IELTS, please visit [Top]

Applicants who have studied for at least two consecutive years in a degree-granting university programme taught entirely in English may submit a substitute document for the English language proficiency score. [Top]

How to Apply

Please refer to the PhD Application Guidelines for detailed instructions on how to apply. [Top]

Key Dates

  • 3 March 2024: Deadline for applications
  • Mid-April 2024: Invitation to an interview and requests for submitting supporting documents by email (shortlisted applicants only)
  • Mid to late April 2024: Interviews (shortlisted applicants only)
  • Late May 2024 onwards: Announcement of application results (successful applicants only)

Dates are subject to change. [Top]


  • Application Processing Fee: None
  • Tuition Fee: USD 12,000 per year*

To secure admission, successful applicants will be required to pay at least 50% of the tuition fee for the first academic year (USD 6,000*, non-refundable) by the due date on the invoice issued after the result announcement and prior to enrolment. Students who choose to pay annually must pay a full one-year tuition payment before the commencement of the academic year. Successful applicants are required to submit all documents and pay the tuition fee by the deadline.**

The estimated total expenses for living and studying in Tokyo for three years are approximately USD 84,000, including tuition fees. Applicants must ensure adequate financial resources to meet the full costs of educational and living expenses.

* The fee is subject to change.

** UNU holidays are listed in the UNU-IAS Academic Calendar. [Top]


The curriculum is reviewed on a yearly basis and the course offerings may not be identical to the ones listed below.

Overview Courses (Compulsory)

  • Trans-disciplinary Graduate Research Seminar I & II
  • Sustainability Science Research Seminar

Elective Courses

  • The United Nations System and Sustainable Development*
  • Global Change and Planetary Boundaries*
  • Principles of International Development Project*
  • Water Resources Systems
  • Education for Sustainable Development: From Global Agendas to Local Actions
  • Understanding the mechanism to implement the Paris Agreement to the UNFCCC
  • Frontier of Sustainability Science
  • Law and Practice of the United Nations
  • Climate Justice and the Right to Education
  • Remote Sensing, Geographical Information Systems and Analysis: Theory and Application
  • Environmental Statistics and Research Methods
  • Studies of Socio-Ecological Production Landscapes and Seascapes
  • From SDGs to Climate Change: Implementation Strategies for its Adaptation and Mitigation

Courses marked with * are held over a short period as part of the UNU Intensive Core (IC) Courses.

Other elective courses may also be offered. A wide range of elective courses offered by partner universities are also available to UNU-IAS students through credit exchange arrangements. [Top]

Diploma Programme for Specialization on the Paris Agreement (SPA)

UNU-IAS offers the SPA Diploma Programme focusing on the implementation of the Paris Agreement mechanisms, such as the enhanced transparency framework, nationally determined contributions, national adaptation planning process, global stocktake and market mechanisms. By strengthening national capacity in these areas, it aims to become an essential means of implementation of the agreement and develop future leaders who will be at the forefront of these vital efforts. The diploma will be granted upon satisfactory completion of the designated courses. [Top]

Joint Diploma Programmes

Students of the UNU-IAS PhD programme are also encouraged to pursue one of two joint diplomas in sustainability science, which are offered in partnership with the University of Tokyo Graduate School of Frontier Sciences (UT-GSFS) and with Sophia University. These diploma programmes require students to gain 18 credits, eight of which must be from courses specified by UNU-IAS and the partner university under the respective joint diploma programme. A joint diploma can only be awarded to students who successfully complete the three-year UNU-IAS PhD degree programme. [Top]

Japan Foundation for UNU (jfUNU) Scholarship

The scholarship is competitive and may be awarded to eligible students who have been accepted for enrolment in the PhD programme. There is no separate application form for the scholarship as it is part of the main online application form for admission. Interested applicants must provide the necessary information and documents for the scholarship when applying to the PhD programme.

I. Coverage

The jfUNU scholarship provides a monthly allowance of 120,000 JPY as a support package for a maximum of 36 months. The tuition fees may be waived for the scholarship recipients.

II. Eligibility Requirements

Applicants must meet the following requirements:

  • Applicants must be from developing countries* who can demonstrate a need for financial assistance.
  • Applicants who are currently living in Japan under a working visa are NOT eligible for the scholarship.
  • Applicants who are already enrolled in other PhD programmes are not eligible. This includes those who have already obtained a PhD degree at an institution other than UNU-IAS.

*Developing countries included in the latest OECD DAC list.

III. Additional Requirements

  • Recipients of the jfUNU Scholarship are required to write a short essay on their learning and experiences at UNU, which is submitted to the donor organisation. Before graduation, each recipient is requested to submit a note of appreciation to the donors with reflections on their future plans.
  • Recipients agree to foster collaboration with jfUNU through participating in jfUNU activities, events, and other opportunities offered to the student body. [Top]


Before contacting the Admissions Office, please read through the Frequently Asked Questions to see if your question has been answered. For any unanswered questions, please use the Inquiry Form. [Top]