Is it a problem if I only have one will in respect of my worldwide assets?
No, as long as the will meets the legal formalities required by the country in which it was signed it will cover the distribution of your worldwide assets wherever situated.
Are there any benefits to having a separate will in each country where I own assets?
Yes, if you as a South African citizen have assets in France for example, a will drawn by a French notary governing your French estate will ensure that same complies with French law and will minimise the chance of problems with the administration of your estate there due to a possible conflict between French and South African law.
It will also avoid delays in the administration of your estate. If you only have one will in respect of your worldwide assets then this original will must first be processed by the legal authority in the country where you live permanently. Once the process is complete, a suitably certified copy of that will would have to be issued for processing by the legal authority in the other country(ies) where you own assets. On the other hand, if you have separate wills in the different countries where you own assets, the processes in each country concerned can commence immediately and simultaneously.
Are there any concerns which I need to take into consideration when having separate wills?
Yes. For example, if a testator deposes to a will in South Africa which limits the scope thereof to his South African estate only and thereafter deposes to another Will in France, the Will in France may revoke the South African will if the testator is not careful when it comes to the wording of the French will.
In addition, if the testator has previously had a French will drafted and wishes to create a new French will, he must ensure that the import of the French is only to revoke his previous French will and not any other will in any other jurisdiction where he has assets.
It is a common misconception that having two wills equates to having two separate estates. An individual only has one (worldwide) estate. Having two wills simply simplifies the administration of the estate in each country and ensures that you receive the best possible legal advice in connection with your affairs in the country concerned. However, from an income tax and inheritance tax perspective, these taxes may be levied on your worldwide assets unless a rebate exists in terms of a double taxation agreement.