Abstract: I will talk about Section 3 of RST's 3rd paper, Sachs's Linkless Embedding Conjecture. Let's say an embedded graph satisfies the "$\pi_1$ Condition" if the complement of every subgraph of it in $S^3$ has free fundamental group. The main result of this section is: an embedded graph is panelled iff it satisfies the $\pi_1$ Condition. This relies on a similar theorem by Scharlemann and Thompson: an embedded planar graph is spherical iff it satisfies the $\pi_1$ Condition.