Traditional methods of data analysis in psychology have long been criticized by scientists and philosophers, the American Psychological Association, and the National Institute for Mental Health. However up to now, no reasonable alternative had been presented. Observation Oriented Modeling (OOM) changes that. OOM is not just another statistical or data analysis methodology that relies upon effect sizes, p levels, or r-squares, but rather a straightforward evaluation of the precise consequences specified by a theory or hypothesis. OOM develops integrated models to accurately explain patterns of observation. Observation Oriented Modeling introduces this new methodology, what it is and does to advance psychology as a science. Numerous examples are presented of how to interpret data using OOM, using free software for the Windows operating system provided to book buyers on an accompanying website. The software offers analysis options to replace t-tests, ANOVA, correlations, multiple regression, mediation analysis chi-square tests, and inter-rater reliability. The output and graphs generated by the software are easy to interpret, and all effect sizes are presented in a common metric: namely the number of observations correctly classified by the algorithm. While flexible and powerful, the software's interface and output are accessible to students at the undergraduate level. Features: Provides a new accurate means of data analysis Offers integrated modeling Contains numerous case examples of models and analysis Free OOM data analysis software Free user instruction manual Software available at our companion Web Site.