Technical Committee 4 on Fracture of Polymers, Composites and Adhesives of the European Structural Integrity Society (ESIS) has been active in the development of fracture mechanics test methods for polymers, composites and adhesives for more than 25 years. Typically the development is pursued via round robin tests on a range of materials performed at several laboratories. Testing is followed by extensive data analysis and adaptation of the test procedure, if necessary, in order to achieve consistent and sufficiently reproducible results. An important issue is the use of the data generated by the application of the test procedures. Comparative materials characterization, e.g., for quality control, or determination of values for data sheets are relatively straight forward. Using fracture mechanics data for design of structures, on the other hand, requires detailed analysis and interpretation. Test development is emphasizing applicability of the test procedure in an industrial test environment. However, during round robin testing, sometimes high-tech equipment and measurement techniques are employed for achieving a sufficient understanding of fracture processes and the parameters affecting them. This has resulted in a number of International Standards for fracture testing (e.g., ISO 13586, ISO 15024, ISO 15850).