According to Wikipedia, a Big Hairy Audacious Goal (BHAG) is a strategic business statement which is created to focus an organization on a single medium-long term organization-wide goal which is audacious, likely to be externally questionable, but not internally regarded as impossible.

With the release of LEED v4, USGBC has outlined seven "impact categories" that it aims to accomplish with this and future versions of the rating system. The purpose of the impact categories is to serve as specific goals in applying the strategies that come with any LEED project.
Strategy, simply put, is what businesses do. In the case of LEED, strategy is what the project teams do in applying the rating systems to buildings, while keeping the impact categories in sight.
LEED v4's seven impact categories are:
The impact categories are not prioritized, from what I could tell, by looking at the outline of LEED v4. Indeed, from reading about LEED v4, its goals are not only to improve the certification experience, but also to do a better job of rewarding projects and project teams that achieve credits that move us (the "Royal us") closer to all of the impact category goals.
Then again, there's that BHAG. In accordance with the definition of a BHAG, which was coined by Jim Collins and Jerry Porras in their book "Built to Last", is a "single medium-long term organization-wide goal which is audacious, likely to be externally questionable, but not internally regarded as impossible." IMHO, LEED's BHAG is to reverse human contribution to climate change. The impact categories may not be specifically hierarchical, but I think the first item on the list is a prerequisite to all the others. And that would make sense, right? After all, LEED has prerequisites and credits. All prerequisites in LEED are required... A project team cannot achieve LEED certification without meeting the prerequisites.
It seems to me that LEED's BHAG, "Reverse Contribution to Global Climate Change" is our prerequisite in our goal of achieving our impact categories. What do you think?
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