Here you can find methods and materials of the Social networks and fertility survey (Sociale relaties en kinderkeuzes), including: 1) A short description on the sample and how it was obtained; 2) A codebook in Dutch (and English translation) with all survey questions and variable names; 3) JavaScript files to produce the GENSI-survey; 4) The link to the survey: https://stulp.gmw.rug.nl/phptmp/survey.php; 5) R-code to process all variables and correct errors in LISS-panel data; 6) R-code to process all alter-alter-relationships and correct errors; 7) csv-files that describe all manual classifications.