The aim of this tutorial is to develop a population PK model and explore covariate relationships of a hypothetical test drug used in the treatment of atrial fibrillation. This case study is part of the Pharmacometrics web-based learning resource from the center for translational medicine of the University of Maryland (https://ctm.umaryland.edu/#/ms-pharma…). The workflow consists of the preparation of a data set, choosing a PK model, estimating parameters and analyzing goodness of fits and results.