Thermography Passive, Active, Pulse and Lockin-thermography will be described along with applications such as water ingress and delaminations in solid composites and honeycomb structures. The mathematical theory and finite element modeling of lockin-thermography of delaminations will be presented and the good correlation with experimental results will be shown. The sensitivity of thermography to delaminations of certain sizes and depths will be presented. Thermography will be compared with “C” scan ultrasound of composites with advantages and disadvantages of both techniques being described so that it will be possible to decide which technique to be used in which situations. Dr B. Stephen Wong is a Senior Research Fellow with Nanyang Technological University. Singapore. Previously he was a lecturer with NTU for 23 years, with the School of Mechanical and Aerospace Engineering, where he presented course modules and conducted research in NonDestructive Testing. Prior to this he worked for 11 years in the UK, conducting research and development and auditing sub-contractors in NDT. During this latter period he worked 2 years for Clarke Chapman - International Combustion Plc Ltd, a pressure vessel fabrication company and 9 years for Rolls Royce Plc Ltd, a gas turbine engine fabrication company. He has a PhD in Physics from the University of Manchester Institute of Science and Technology, UK and has published over 90 papers in various journals and conferences mainly in non-destructive testing. He is a Member of the Overseas Advisory Panel for the British Institute of NDT for Singapore and is a Technical NDT auditor for the Singapore Laboratory Accreditation Service. He has collaborated with various companies (including RSAF and GE, USA) on NDT projects for many years.