Many changes occurred in agricultural patterns in the Republic of Ireland between 1950 and 1971. Changes in general land-use patterns, crop acreages, livestock numbers, farm size distributions and levels of mechanization are discussed in this paper. The emphasis in the paper is on examining by principal components analysis the inter correlations between 27 indicators of change. The principal component was identified as describing the trend towards intensification and consolidation in agri culture, which displayed marked east-west contrasts. Other components identified related to per sistence of traditional tillage practices and trends in particular crop and livestock patterns. The spatial pattern of scores on these components was more complex. To conclude the study a grouping procedure has been used to collapse the individual patterns for each component onto a single map that highlights the complexity of regional patterns of adjustment in agriculture. The paper also serves to illustrate the usefulness of principal components analysis and cluster analysis for summarizing large data sets.