The basic principles and practices of SMMR are introduced based on the simplest scenario that one can encounter in applied social science research: a single sufficient condition. The main types of cases and various fundamental principles of SMMR are detailed, the same as the first formulas introduced that distinguish better from worse cases for within-case analysis if fuzzy sets are used. Learning goals: - Understand how membership of cases in the QCA solution and the outcome is used for sorting cases into one of the four basic case types - Learn about the first set of SMMR principles that guide the selection of cases for within-case analyses on the mechanism linking the condition to the outcome - Get acquainted with the seven possible SMMR designs: three single-case and four comparative SMMR designs - Become familiar with the basic logic of the smmr() function - Learn about formulas distinguishing between better and worse case choices for within-case analyses - Understand the different scenarios in which a typical and an iir case can hold membership in the condition, the outcome, and the mechanism and the implications of these scenarios for causal inference