This book offers a theoretical and practical picture of the main issues related to the quality of the summary document. In the first two chapters, the document summary and the quality criteria corresponding to it are discussed in theory with numerous references to the Spanish and international literature, both documentary and linguistics. Follow a specific case evaluation summaries databases education and agriculture data from various sources. In particular, the summaries are evaluated from the point of view of potential users and the modern media. In the conclusions, the service managers find practical information to improve the quality of the summary document suggestions, and students and researchers of documentation, proposals for further research in the area of ​​knowledge.