Andrew Flower


20 Rue Cambon
75001, Paris, France


Peers and clients say:

"A very strong economist who is very active in arbitration"
"He's great when giving evidence and knows when to make appropriate concessions"


Andrew has over 30 years’ experience providing expert evidence on damages in international arbitration – commercial and investor-state. He has provided oral evidence in over 40 arbitrations and written evidence in over 150. He has been appointed by the ICC Centre of Expertise; approved by parties as tribunal expert; assisted parties in post-transaction disputes and acted as determining expert. Andrew was previously the global head of disputes at a big four firm. Andrew speaks English and French.

What sorts of matters are you most active on at present?

Throughout my career, I have worked on a wide variety of matters, both geographically and by industry. Certainly, one sees hot spots from time to time (renewables and government regulation, for example) but the broad spread remains across both commercial and investor-state matters. Long may this continue, as it’s one of the fascinating elements of the work. Often in arbitration there is a substantial delay between the causal event and the dispute – for example, the various disputes arising out of the Arab Spring and what followed.

Which key qualities and attributes do successful expert witnesses need to possess?

I’ve said previously that the expert community has been getting a bad rap of late: either for being ships passing in the night or showing an unwillingness to work with opposing experts. However, I do feel that experts need to recognise the fundamental importance of their “independence” from this paying client – in the sense of not being willing to take unsubstantiated or evidently extreme positions. All this helps individual experts demonstrate their “reasonableness” to tribunals.

What are the main challenges you face when resolving complex damages questions?

Without delving too much into the technical, I think there are three main issues. The first is simply ensuring that there is evidence to support your damage assessment. The second is to ensure that it is grounded and reasonable. We all know it is too easy for a DCF to be effectively “rubbish in – rubbish out”: an immediate question I ask on looking at a DCF is how has it been tested by reference to other valuation methodologies? Lastly, how do we tackle so called “black swan” events. The answer to this can wait for next year.

How would you characterise the current perception of expert witnesses in the market?

As noted above the expert community has been getting a bad rap of late: either for being ships passing in the night or showing an unwillingness to work with opposing experts. One thing that might help change is more disclosure and commentary by tribunals in awards (and thus the press) on whether experts have been helpful in assisting tribunals render awards and on the quality of their evidence generally. This ties to the general move to greater transparency we are seeing in arbitration as a whole.

Where do you think expert witnesses work is headed in the future?

My career has developed in an era where the expert witness has changed from being a loose group of hobbyists who did the work as a side-line to a cadre of “professional” experts assessed by various publications such as this. This trend is only going to continue with further specialism in many areas over issues of industry, regulation and geography. I do think there will remain a core role for generalists where an understanding of damages theories remains core.

Do you have any tips for counsel on how to use an expert team effectively?

Engage early! While not compromising the independence of the expert and their responsibility to the tribunal, it does allow an expert (and their team) the time to provide input and advice on the preparation of a claim (or its defence) to the client. There can be significant cost and time savings in so doing, even if there is an element of upfront investment. We are seeing this as third-party funding becomes increasingly important.

What steps can senior practitioners take to assist the next generation of experts?

I think it is critical that senior practitioners look to bring on younger practitioners and to create a legacy. This requires them to pass on contacts to the next generation of experts and to ensure that this next generation has the opportunities I had – to give evidence themselves and to be part of the class of “future leaders”.