A software engineering research study has been undertaken to empirically analyze and compare various software development approaches; its fundamental features and initial findings are presented in this paper. An experiment was designed and conducted to confirm certain suppositions concerning the beneficial effects of a particular disciplined methodology for software development. The disciplined methodology consisted of programming teams employing certain techniques and organizations commonly defined under the umbrella term structured programming. Other programming teams and individual programmers both served as control groups for comparison. The experimentally tested hypotheses involved a number of quantitative, objective, unobtrusive, and automatable measures of programming aspects dealing with the software development process and the developed software product. The experiment's results revealed several programming aspects for which statistically significant differences existed between the disciplined methodology and the control groups. The results were interpreted as confirmation of the original suppositions and evidence in favor of the disciplined methodology. This paper describes the specific features of the experiment; outlines the investigative approach used to plan, execute, and analyze it; reports its immediate results; and interprets them according to intuitions regarding the disciplined methodology.