First nationally representative, fully probabilistic survey of inter-generational social mobility in Mexico. The main objective of the ESRU SMSM is to describe and analyze inter-generational socioeconomic mobility in Mexican society. Collects information on the socioeconomic standing of the respondent and his/her spouse or partner, including education, occupation, income, assets, and wealth. Also includes information on the socioeconomic standing of the respondent's and his/her spouse/partner's parents and conditions when they were growing up. Additional topics include: international and domestic migration, health, occupational trajectory, opinions, and attitudes.