  We construct vortex loop operators in the three-dimensional N = 6
supersymmetric Chern-Simons theory recently constructed by Aharony, Bergman,
Jafferis and Maldacena. These disorder loop operators are specified by a
vortex-like singularity for the scalar and gauge fields along a one dimensional
curve in spacetime. We identify the 1/2, 1/3 and 1/6 BPS loop operators in the
Chern-Simons theory with excitations of M-theory corresponding to M2-branes
ending along a curve on the boundary of AdS_4 x S^7/Z_k. The vortex loop
operators can also be given a purely geometric description in terms of regular
"bubbling" solutions of eleven dimensional supergravity which are
asymptotically AdS_4 x S^7/Z_k.
