  We study the 2-dimensional uniform prudent self-avoiding walk, which assigns
equal probability to all nearest-neighbor self-avoiding paths of a fixed length
that respect the prudent condition, namely, the path cannot take any step in
the direction of a previously visited site. The uniform prudent walk has been
investigated with combinatorial techniques in [Bousquet-M\'elou, 2010], while
another variant, the kinetic prudent walk has been analyzed in detail in
[Beffara, Friedli and Velenik, 2010]. In this paper, we prove that the
$2$-dimensional uniform prudent walk is ballistic and follows one of the $4$
diagonals with equal probability. We also establish a functional central limit
theorem for the fluctuations of the path around the diagonal.
