I'll describe some joint work with John Verzani, on conditioning super Brownian motion (SBM) via its exit measure. In high dimensions, we condition on the support of the exit measure hitting a given finite collection of points, and represent this process in terms of a tree-like backbone throwing off mass. The goal is to give an explicit dynamic description of this tree. Along the way, I'll review LeGall's construction of the super Brownian excursion.