De or het plateauplanning?

The correct Dutch article is:

de plateauplanning

Rule Words ending in -ing: almost always de. See the rule

How to use plateauplanning

the plateauplanningde plateauplanning
this plateauplanningdeze plateauplanning
that plateauplanningdie plateauplanning
our plateauplanningonze plateauplanning
your plateauplanningjouw plateauplanning
every plateauplanningelke plateauplanning
which plateauplanning?welke plateauplanning?
a big plateauplanning / the big plateauplanningeen grote plateauplanning, de grote plateauplanning