Using examples from clinical studies in psychology and medicine, we review the basic study design in clinical trials, including statistical tests and sample size planning. Step by step we learn how to extend the methodology to adjust for baseline performance, to analyze subgroups, to do interim analyses, to test for equivalence instead of difference, to deal with missing data, to deal with multiple outcome variables, to analyze binary data, count data, and event times, to deal with clustered data (e.g. group therapy), and to compare natural (i.e., not randomized groups). In the end, students will be able to plan and analyze of standard study designs in real world-settings, including basic preprocessing of data, import and export of different files, and standardized reporting. Most of the analyses will be done with SPSS, but the participants will also acquire some very basic R skills.