Spanish research in Documentation (or Library and Information Science, LIS) began to stand out in the 1980s, in parallel with the creation of university studies in Library and Information Science, and it increased its activity significantly until the year 2000. In this period, research in Documentation was oriented to disseminate rather than innovate, and also had a low international impact, shortage of economic and human resources, and poor methodological quality. In the first 20 years of the 21st century, we have witnessed an outstanding growth and diversification of this research activity, which has led to the overcoming of most of the problems mentioned before. The objective of the text is to present a general overview of the development of Documentation research in Spain in the last 20 years based on the analysis of five fundamental aspects: publications (articles and monographs), topics and methodologies, scientific journals, research projects and doctoral theses. General descriptive data from public statistical sources and comments from a bibliographic review are provided for each of them. As a conclusion, a very positive global balance of Spanish research in Documentation in the last 20 years stands out, not only a quantitative increase (in publications, theses, research projects, etc.) but also a qualitative improvement in the use of research methods and techniques, as well as a diversification of the research topics. In any case, internationalization (collaboration with foreign authors) and the presentation of international projects could be improved. Finally, there is a risk in near future related to aging and the absence of generational renewal of the research staff that can will slow down this growth. [ABSTRACT FROM AUTHOR]