  A digraph is 2-regular if every vertex has both indegree and outdegree two.
We define an embedding of a 2-regular digraph to be a 2-cell embedding of the
underlying graph in a closed surface with the added property that for every
vertex~$v$, the two edges directed away from $v$ are not consecutive in the
local rotation around $v$. In other words, at each vertex the incident edges
are oriented in-out-in-out. The goal of this article is to provide an analogue
of Whitney's theorem on planar embeddings in the setting of 2-regular digraphs.
In the course of doing so, we note that Tutte's Theorem on peripheral cycles
also has a natural analogue in this setting.
