  Emergent bath-mediated attraction and condensation arise when multiple
particles are simultaneously driven through an equilibrated bath under
geometric constraints. While such scenarios are observed in a variety of
non-equilibrium phenomena, with an abundance of experimental and numerical
evidence, little quantitative understanding of how these interactions arise is
currently available. Here we approach the problem by studying the behavior of
two driven "tracer" particles, propagating through a bath in a 1D lattice with
excluded-volume interactions. We analytically explore the mechanism responsible
for the tracers' emergent interactions and compute the resulting effective
attractive potential. This mechanism is then numerically shown to extend to a
realistic model of hard driven Brownian discs confined to a narrow 2D channel.
