Fergus O'Dowd (Louth, Fine Gael) | Oireachtas source

I am just talking about the two words together. A verbal distinction is made between guidelines and instructions. I presume an instruction is something that is mandatory; that one must do. A guideline specifies that one must have regard to an issue and a decision must be within those parameters. A guideline as opposed to an instruction allows some flexibility on the outcome.