Originally published in 1989, this book provides a comprehensive account of how to handle astronomical data. Descriptions of data acquisition, handling, and interpretation are included. The advice starts with chapters on observatories and observations, followed by discussions on the archiving of data and its presentation in the literature. There are many useful suggestions on the nomenclature of astronomical objects, and descriptions of the astronomical catalogues. Three chapters concentrate on databases and astronomical data centres. Finally the author comments on publication and the growth of astronomical data. The clear advice given in this book will be of interest to professional astronomers and graduate students who handle data.