The collecting of survey data presently faces a great methodological challenge as today, more than ever before, researchers are confronted with a constantly declining willingness among people to participate in surveys (unit - non-response). New possibilities for data collection must be developed and thoroughly researched. An example of this new type of data collection is the online questionnaire, either as a unique survey method or in combination with telephone surveys (Mixed-Mode design).

Non-response research by GESIS focuses on developing strategies for increased survey participation. The underlying goal of this research is determining the pros and cons of internet surveys compared with the extant survey techniques, and specifically to determine the best attributes of an online-access panel.