Tax Question for U.S. Retiree

There seems to be lots of info on the internet on the subject.  I copied this: 

Double Taxation
Double tax treaties exist that may provide tax relief where a Belgian tax resident also pays income tax in another country.

Tax Treatment of Expatriates Assigned to Belgium
Expatriates may qualify for a special tax regime. If expatriate status is granted by the tax authorities, the person is considered as a non-resident of Belgium for tax purposes.

In addition, an expatriate may receive the following allowances free of income tax, capped at €11,250 (managers) or exceptionally at €29,750 (scientists):

Cost of living (limited to €2,500)
Cost of housing
Tax equalisation
School fees (uncapped)
Since the qualifying expatriate is treated as a non-resident, his foreign-sourced income is not taxed in Belgium. Earned income connected to an activity that is carried out outside Belgium is therefore not taxed (this is the travel exclusion).

Thanks for the post Pamela. I have also seen similar info on the Internet, however have not found anything that specifically recovers a retirement pension.

As you indicate above the tax treaties cover double taxation on "income" or earnings but I've yet to find any info on retirement income.

Thanks for the post!