What is the best way for companies to go about getting a centralized oversight of their benefits offering? We have 37 countries all running their benefits portfolio in isolation from each other. It would be great to hear other's experiences and the approach taken.

It can be surprisingly difficult can't it.  Mostly I think because not everyone has the same idea of what a benefit is.  When you ask a location for a list of benefits, you get the obvious ones - insurances, time off, etc.  

But only when you really dig deep do you find that in one location you get a day off for your wedding (not written down anywhere, but a massively valued benefit), or long service awards include a party at the end of the year, or everyone gets the first friday in the month to focus on learning something new, etc.  All very valued benefits, but not necessarily recognised as such when the center asks for a list.

I'm sorry to say but if you really do want to get to the actual list of benefits you need to workshop it with a few people from each location.

And of course it changes every year (at different times of the year for different benefits and in different countries), so if you're not careful you're always working off something out of date.  

I guess you've got to be very clear what problem you're trying to solve before you head into something that's a lot trickier than it initially appears to be.

I love this question. I have just finished going through this exact process. Different offices are at various levels of maturity and benefits norms differ globally. This is a contentious issue as no one wants to give up a benefit. My team assessed what we had globally. Ran focus groups to establish what demand was there and gathered market intel for our sector. We then ran a fairness and equity rule across the regions. Your aim should be engagement through benefits but as much of a level playing field as possible.
Once you have this you can use a platform to manage the benefits such as Zest