You can download our rules here:

VIAC Rules of Investment Arbitration and Mediation 2021 English - Online Version 
VIAC Rules of Investment Arbitration and Mediation 2021 English

VIAC Rules of Investment Arbitration and Mediation 2021 German - Online Version
VIAC Rules of Investment Arbitration and Mediation 2021 German



VIAC Rules of Investment Arbitration and Mediation 2021 Turkish


Please read the Kluwer Arbitration Blog post  "VIAC Rules Revision 2021 Part II: The New VIAC Rules of Investment Arbitration and Mediation" by Veronika Korom and the article "Vienna International Arbitral Centre launches new investment arbitration and mediation rules" by Lucia Raimanova and Peter Plachy.


A new version of the VIAC Rules of Investment Arbitration and Investment Mediation entered  into force on 1 July 2021 (“Vienna Investment Arbitration Rules and Vienna Investment Mediation Rules 2021“; short “VRI” and “VMRI”). The Rules applies to all proceedings that commenced after 30 June 2021 or will commence in the future.

A working group – to whom we are tremendously grateful - consisting of representatives of the VIAC Board and Secretariat, led by our Board member Claudia Annacker, has drafted these new rules of procedure (Alice Fremuth-Wolf, Günther Horvath, Johanna Kathan-Spath, Dietmar Prager, Lucia Raimanova, Franz Schwarz, Nathalie Voser). VIAC’s legal counsel, Johanna Kathan-Spath, has orchestered the project of the rules revision, investment and commercial, and a special thanks goes to her for all the work.

Claudia Annacker on the new investment rules:
“Combining the advantages of specialized investment arbitration rules with the procedural flexibility afforded by the Vienna Rules, the Vienna Investment Arbitration Rules are an effective response to the unique demands of investment arbitration. 

The Vienna Investment Arbitration Rules are a comprehensive, standalone set of arbitral rules based on the standard Vienna Rules, but feature a number of innovations and modifications to accommodate the fundamental differences between commercial and investment arbitration, including a right of non-disputing contracting States to make written submissions on questions of treaty interpretation. 

The Vienna Investment Arbitration Rules facilitate efficient resolution of investment disputes and take head on two major concerns of users of investment arbitration, duration and cost: 

There are no objective requirements regarding the parties and the nature of the dispute; parties are entirely free to decide for themselves whether a dispute is an investment dispute that they wish to resolve under these rules. Manifestly unmeritorious claims, counterclaims, and defenses can be dismissed expeditiously. Tribunals must render awards no later than six months after the last hearing or the filing of the last authorized submission. 

Critically, the Vienna Investment Arbitration Rules offer significant cost advantages and are thus particularly suitable for smaller investment claims, which often fall through the cracks.” 

Franz Schwarz, Vice-President of the VIAC Board:
“It was always a hallmark of the Vienna Rules to provide a safe and efficient forum that respects party autonomy and procedural flexibility and avoids the kind of over-regulation that hinders rather than supports effective dispute resolution.  VIAC has now applied that successful formula to investment disputes, setting up a modern, streamlined and highly effective framework for disputes between states and investors.” 

Lucia Raimanova:
„An affordable and progressive alternative, which works also for investment disputes of lower value.“ 

Nathalie Voser:
"It was high time that a European Arbitration Institution issued specific investment arbitration rules since even the best commercial rules cannot be suited for the specific interests at issue in investment arbitration. VIAC was particularly suited for this task already because of its closeness to Eastern European States and investors who will have a particularly interest in such a set of arbitration rules.”

It is largely based on the well-tried concept of the VIAC Arbitration and Mediation Rules for commercial disputes ("Vienna Rules and Vienna Mediation Rules"), supplemented by special features that are essential to investment proceedings.

An overview of the key features of the new rules on investment procedures can be found here: