Setting limits?

Short of having a heart attack while working at one's desk, how do faculty convey to higher administrators (chairs, deans, etc.) when you are at (or beyond) the limits of what we can take on?
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The hope is that this can be a clarifying contribution to being careful and strategic about what we take on and what we ask others to take on.

A. For each priority below in turn, take stock with colleagues% in our units of whether we are fulfilling this well and plan what we need to improve to do so.* One way to convey our limits is to communicate that we are not ready to move on to the next priority if we are not yet able to give ourselves a green light on the priorities that come before it:

B. Do not attend any meeting without a clear agenda and pre-circulated materials to prepare for efficient use of the face2face time together. (In this spirit, do not convene a meeting unless you have time to define a clear agenda and pre-circulate materials so participants can prepare for efficient use of the time together.) (Peter Taylor)