The main purpose of current study is to review the main existing methodological approaches to the integration of survey data and digital traces that are used in sociological research. The paper examines key arguments in the current methodological discussion about the place of big digital data in contemporary social science research. The authors make an attempt to scrutinize the practice of integrating survey data and digital traces through the concept of “reactive – nonreactive” measurement. The possible functions of digital traces in the design of the study are indicated (on the example of social media data). On the example of three research areas (the study of media consumption, media effects and electoral behavior) general methodological principles for integrating data of different nature are demonstrated and possible prospects for the development of these approaches is described. The article discusses a wide range of methodological issues: problems of the data linking validity; potential threats to the validity of digital traces; opportunities to improve survey questionnaire, to enrich data, to search for new valid indicators of socio-political processes and to provide cross-validation of research results. The current practices of integrating administrative data are considered as well.