Being in a tiny country with 4 official languages, I know it's very often a customer need their content written in several languages.
At Virtuaza, we use WPML¤, a multilingual plugin for WordPress, for the customers who need that. It's available both for our customers with a standalone WordPress installation and in the virtuaza.net multisite plateform. On the multisite plateform, customers also often need to map their domain, for example pjmartin.lessites.ch is now pjmartin.ch thanks to a plugin called Domain Mapping by WPMUDev.
When I was in Leiden for the first WordCamp Europe back in October 2013, I met Amir Helzer, from WPML, just after his presentation with developers of other multilingual plugins.
We talked a bit, and I told him that in the case of Virtuaza, both plugins WPML and Domain Mapping were working very well together. The use of both plugins together seem to have been an issue for several of their customers, so Amir asked me if I could talk with one of WPML staff person about it.
See the result here : Maintaining client sites centrally using WPML and Domain Mapping – February 7th, 2014 by Agnes Bury
it's a great case study post and Agnes has been very friendly and professional interviewing me via video chat and lot of emails.
You can also read what I said on WPMUDev's forum about it.
If you use those both plugins on your WordPress installation, we hope this case study is helpful to you, do not hesitate to comment here or on WPML's post if you have a question.
If you need such a multisite with WPML and domain mapping, and several other options to run a plateform, but you do not want to do it yourself, I'm available to do it for you, please contact me for a quote.
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