This project, sponsored by the BBV Foundation (Banco Bilbao-Vizcaya), Cajamadrid and BBK (Bilbao Bizkaia Kutxa), and conducted by ASEP, consisted in 52 monographic surveys with representative samples of the Spanish population on different topics of academic interest between 1990 and 1996, and whose data files were distributed (in diskette) free of charge to 250 Spanish and 150 foreign research institutions (including international data archives) in orde to stimulate empirical research on Spain.