These draft operational procedures are for active thermography techniques applied to non-destructive testing of CFRP and GFRP composite structures. By actively heating the samples under test using an optical excitation source, inhomogeneities can be detected and characterized form the measurement of the spatial and temporal temperature distribution at the surface using an infrared (IR) camera. The aims of testing are: •Detection of defects, inclusions and inhomogeneities •Detection of reduced material thicknesses •Determination of the detectability by SNR values •Determination of lateral defect position and size •Determination of defect depth (coverage) The draft operational procedures are related to the following active thermography techniques: •Pulse or flash thermography (PT) •Step heated thermography (SHT) •Lock-in thermography (LT) Usually, the measurements are performed in reflection configuration, i. e. optical excitation source and IR camera are positioned at the same side of the test specimen. This is required if only single sided access to the structure is possible. Nevertheless, measurements in transmission configuration, i. e. optical excitation source and IR camera are at opposite sides of the test specimen, can be performed as well. This draft operational procedure consists of a general description, a test instruction and a template for the protocol for each technique.