International collaboration in the development and production of defen
ce equipment is said to reduce procurement costs and improve export pr
ospects. However, critics argue that joint ventures cost more than nat
ional programmes, are more prone to cost escalation and take longer to
complete. These claims are evaluated by comparing collaborative and n
ational military aircraft using a variety of performance indicators. T
he evidence suggests that for military aircraft collaboration leads to
cost savings and greater scales of output, with only limited support
for the view that joint projects take longer to develop. There is litt
le evidence that collaborative projects perform better in export marke
ts than their national rivals.