The purpose of this research report is to bring together the complete set of data on income and productivity for the New Zealand agricultural sector for the period 1921-1967. It is anticipated that the resulting tables will be of interest to those concerned with policy-making and those who wish to examine past trends for their own purposes. In this introduction we outline the order in which the material appears, the conceptual viewpoint taken of the agricultural sector, and the definition of terms. In the second section, we set out a brief discussion, with the relevant graphs, of some of the main trends which the data show. Since further analysis of the data is obviously desirable, we conclude these introductory sections with a bibliography of papers so far prepared in this Department on the general theme of agricultural productivity.