Citations and related work are crucial in any research to position the work and to build on the work of others. A high citation count is an indication of the influence of specific articles. The importance of citations means that it is interesting to analyze which articles are cited the most. Such an analysis has been conducted using the ISI Web of Science to identify the most cited software engineering journal articles published in 1999. The objective of the analysis is to identify and list the articles that have influenced others the most as measured by citation count. An understanding of which research is viewed as most valuable to build upon may provide valuable insights into what research to focus on now and in the future. Based on the analysis, a list of the 20 most cited articles is presented here. The intention of the analysis is twofold. First, to actually show the most cited articles, and second, to invite the authors of the most cited articles in 1999 to contribute to a special issue of Information and Software Technology. Five invited authors have accepted the invitation and their articles are appearing in this special issue. Moreover, the research topics and methods of the most cited articles in 1999 are compared with those from the most cited articles in 1994 to provide a picture of similarities and differences between the years.