Seed dormancy and germination are generally ill-defined phenomena since their occurrence and completion is measured almost exclusively by protrusion of (usually) the radicle through the surrounding tissues. This has hampered significant progress in our understanding of mechanisms and regulation of dormancy and germination. Fortunately, modern molecular-genetic approaches, including genomics, have immensely accelerated the acquisition of relevant data to deepen our insights. However, the vast amount of data that is available threatens to blur our minds rather than present us with the clear picture that we pursue. To avoid this, it is necessary to retrieve the truly relevant questions, assess if the system under investigation is suitable to address these questions and, if so, whether these systems are properly used. This chapter provides a short survey of recently acquired data for Arabidopsis (Arabidopsis thaliana (L.) Heynh.) dormancy and germination, with an emphasis on the role of abscisic acid (ABA).