International reply stamps: can u put in ordinary stamps?

instead of international reply stamps (they dont know what that is at my post office) is it possible if you send a letter abroad (and want to receive one back), to add 'normal' poststamps in the envelope? i mean, if i want to send something abroad it works just fine if i put on normal poststamps from my country, but will that be valid if someone in america for instance uses dutch (europe) stamps and to send something to holland?