  Space-time wormholes were introduced in Wheeler's idea of space-time foam.
Traversible wormholes as defined by Morris & Thorne became popular as potential
short cuts across the universe and even time machines. More recently, the
author proposed a general theory of wormhole dynamics, unified with black-hole
dynamics. This article gives a brief review of the above ideas and summarizes
progress on wormhole dynamics in the last year. Firstly, a numerical study of
dynamical perturbations of the first Morris-Thorne wormhole showed it to be
unstable, either collapsing to a black hole or exploding to an inflationary
universe. This provides a mechanism for inflating a wormhole from space-time
foam to usable size. Intriguing critical behaviour was also discovered.
Secondly, a wormhole solution supported by pure radiation was discovered and
used to find analytic examples of dynamic wormhole processes which were also
recently found in a two-dimensional dilaton gravity model: the construction of
a traversible wormhole from a Schwarzschild black hole and vice versa, and the
enlargement or reduction of the wormhole.
