Applications for September 2026 entry are now open. The deadline for applications is 11 February 2026. Prospective students are strongly encouraged to attend the online information session on 9 December 2025.
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.
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);
OR
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 2026 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 IELTS 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). Applicants are expected to submit valid scores by the application deadline (27 February 2026).
** TOEFL IBT will introduce an updated score scale (1–6). For 2026 admissions, scores will be reviewed on the scale of 0–120.
- TOEFL: Please order an official score report using the institution code D317. Please visit the TOEFL website for more information.
- IELTS: Please request an official report be sent directly to UNU-IAS. Please visit the IELTS website for more information.
Applicants meeting below criteria may submit a substitute document for the English language proficiency score:
- Applicants who have studied for at least two consecutive years in a degree-granting university programme taught entirely in English may submit substitute document for the English language proficiency score. If this is your case, you must provide a certificate from your university stating that English is/was your unique language of instruction. An original of the certificate must be submitted directly to UNU-IAS by 27 February 2026.
How to Apply
Please refer to the PhD Application Guidelines for detailed instructions on how to apply.
Key Dates
- 11 February 2026: Application form submission deadline
- 27 February 2026: Deadline for submission of supporting documents
- Mid-Late March 2026: Interview invitation email (shortlisted applicants only)
- Early to Mid-April 2026: Interviews (shortlisted applicants only)
- Late May 2026 onwards: Application results announced to successful applicants only
Dates are subject to change.
Fees
- 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.
In addition to the tuition fee and living costs mentioned above, applicants should budget for travel expenses to Japan and the initial living costs for settling into a new environment. Scholarship recipients should also ensure they have sufficient funds to cover travel and living expenses for first one to two months. Please refer to the scholarship section on this page for details.
* The fee is subject to change.
** UNU holidays are listed in the UNU-IAS Academic Calendar.
Courses
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 I & II
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
- Enhanced Climate Action through High Integrity Carbon Markets: Practicum on the Implementation of the Paris Agreement Article 6 **
- The 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: Integrating SDGs into Climate Change Actions
- Climate Change Mitigation through the Measurement, Reporting and Verification (MRV) of Greenhouse Gas Emissions: Practicum on the Implementation of the Paris Agreement **
Courses marked with * are held over a short period as part of the UNU Intensive Core (IC) Courses.
Courses marked with ** are courses in the pool of Diploma Programme for Specialization on the Paris Agreement (SPA). Details can be found below.
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.
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.
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.
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 when applying to the PhD programme.
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 scholarship recipients.
Eligibility Requirements
Applicants must meet the following requirements:
- Applicants must be from ODA recipient 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.
*ODA recipients are included the latest OECD DAC list.
Additional Requirements
- Recipients of the jfUNU Scholarship are required to write a short essay on their learning and experiences at UNU to be submitted to the donor organization. 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.
FAQ & Inquiries
Before contacting the Admissions Office, please read the Frequently Asked Questions to see if your question has been answered. For any unanswered questions, please use the inquiry form at the bottom of this page.
Please note that due to the high volume of inquiries and limited resources, it may take 1–2 weeks to receive a reply. Applicants are strongly encouraged to start the process early and submit questions well in advance, as replies cannot be guaranteed by the application deadline (11 February 2026 JST).