  Recent experiments on the organic compound $\kappa-(BEDT-TTF)_2 Cu_2 (CN)_3$
raise the possibility that the system may be described as a quantum spin
liquid. Here we propose a pairing state caused by the `Amperean' attractive
interaction between spinons on a Fermi surface mediated by the U(1) gauge
field. We show that this state can explain many of the observed low temperature
phenomena and discuss testable consequences.
