One approach to testing the suitability of an adhesive joint for a par
ticular application is to build and test to destruction a representati
ve sample of the joint. In this way the best adhesive and surface trea
tment for a given application can be found. To reduce the costs of thi
s approach, the designer will wish to call on previous experience with
adhesives, surface treatments, and joint designs so as to reach a hig
h probability of success before he builds and tests a structural proto
type. If structures are expensive, it will be difficult to justify mor
e than a very limited series of prototype tests before production begi
ns, During the production phase, and also in service with critical str
uctures, it is essential to use nondestructive tests to assess the qua
lity and fitness for purpose of the product. The nondestructive test w
ill not measure strength directly but will measure a parameter which c
an be correlated to strength. It is therefore, essential that a suitab
le nondestructive test is chosen and that its results ave correctly in
terpreted. In this paper, typical defects found in adhesive joints are
described together with their significance. The limits and likely suc
cess of current physical nondestructive tests are described, and futur
e trends outlined. (C) 1997 Elsevier Science Ltd.