This article considers the preventive flow interception problem (FIP) on a
network. Given a directed network with known origin-destination path flows,
each generating a certain amount of risk, the preventive FIP consists of o
ptimally locating m facilities on the network in order to maximize the tota
l risk reduction. A greedy search heuristic as well as several variants of
an ascent search heuristic and of a tabu search heuristic are presented for
the FIP. Computational results indicate that the best versions of the latt
er heuristics consistently produce optimal or near optimal solutions on tes
t problems. (C) 2000 John Wiley & Sons, Inc.