  In this paper, we construct the associated vertex operator algebras for all
$\mathcal{N}=2$ superconformal field theories of rank one. We give a uniform
presentation through free-field realizations, which turns out to be a
particularly suitable framework for this task. The elementary building blocks
of the construction are dictated by the low energy degrees of freedom on the
Higgs branch, which are well understood for rank-one theories. We further
analyze the interplay between Higgs and Coulomb data on the moduli space of
vacua, which tightly constrain the overall structure of the free field
realizations. Our results suggest a plausible bottom-up classification scheme
for low-rank SCFTs incorporating vertex algebra techniques.
