In Spain you are forced to retire at 65. If prior to that you fail your medical validations then you are considered "active reserve" and can not perform atco duties but remain within the ANSP making other related jobs (and about 50% salary).
However this is not something definitive, these conditions where "agreed" upon through an arbiter whose ruling is set to expire 2013, so expect these conditions to change for the worse.
For example, in may 2010 a law was passed declaring automatically, from one day to the next, all atcos above 56 unfit to work. This was reversed later the same year as this meant there weren't enough atcos... but expect a revival of this once there are.
Retirement conditions in Spain? Wish we'd know...
