In my experience, sometimes your best option is to act like you have the authority to provide that guidance.
While this doesn’t work in all corporations or for all decisions, if there’s a decision-making vacuum and you lack the personal power to make the decisions, act as though you have the authority and begin acting in accordance with what you think the decision ought to be. At that point, one of the following should happen:
* Best case, your decision is respected and the results are carried out
* Less good case, someone else disagrees with the decision and says what should REALLY be happening, at which point the decision is made and there’s clear guidance (even if your original decision isn’t respected)
* Worst case, someone else says you’re not allowed, but nobody actually makes the decision
I usually get one of the first two as a result, as either it provides the necessary guidance or lights a fire under the person who should be making the decision. I will say, however, that it can result in some hard conversations, depending on how territorial the functional manager who *should* make the decision is!