The present report documents the procedures used in compiling the United Nations Database on the Living Arrangements of Older Persons 2017, and summarizes some of the key findings from the data. Section II describes the major sources of empirical data and methods used to estimate four categories of older persons’ household living arrangements: alone, with a spouse only, with their children, or other household arrangements. Section III describes some of the general patterns revealed by the estimates across countries and regions, including those related to sex- and age-differences in older persons’ living arrangements, as well as observed trends in older persons’ households between the period circa 1990 and that circa 2010. Section IV offers some remarks on priorities for data and research over the near term to advance the work of the United Nations on older persons’ living arrangements. Annexes I and II address measurement concerns encountered in developing the dataset, including the potential role of trends in co-residence with minor children in influencing the trends described in section III, as well as the potential underestimation of co-residence with children from certain household surveys. Annex III lists estimates of institutional living arrangements among older persons for a subset of countries. Preface -- 1. Introduction -- 2. Data and methods -- 3. Key findings -- 4. Final remarks -- Annex 1. The potential influence of co-residence with minor children on estimated trends in older persons’ living arrangements -- Annex 2. Methodological note on the possible underestimation of older persons co-residing with their children -- Annex 3. Prevalence of institutional living arrangements.