We study the asymptotic behavior, as a small parameter
ε
\varepsilon
goes to
0
0
, of the minimizers for a variational problem which involves a “circular-well” potential, i.e., a potential vanishing on a closed smooth curve in
R
2
\mathbb {R}^2
. We thus generalize previous results obtained for the special case of the Ginzburg-Landau potential.