This review discusses the molecular control of seed dormancy, germination, after-ripening, and imbibition in *Arabidopsis thaliana*. The establishment of dormancy during seed maturation is regulated by networks of transcription factors with overlapping and discrete functions. After-ripening, which follows desiccation, determines germination potential, and recent studies suggest that transcriptional and post-transcriptional processes occur in dry seeds. The single-cell endosperm layer surrounding the embryo plays a crucial role in maintaining dormancy, and transcriptomics approaches are uncovering endosperm-specific genes and processes. Hormone signaling pathways have been extensively studied, but hormone-independent pathways and natural variation in key regulatory loci are also important. Environmental signals, particularly light, and moist chilling (stratification) are increasingly understood at the molecular level. The review highlights the importance of postgenomics, physiology, and molecular genetics in understanding these processes.This review discusses the molecular control of seed dormancy, germination, after-ripening, and imbibition in *Arabidopsis thaliana*. The establishment of dormancy during seed maturation is regulated by networks of transcription factors with overlapping and discrete functions. After-ripening, which follows desiccation, determines germination potential, and recent studies suggest that transcriptional and post-transcriptional processes occur in dry seeds. The single-cell endosperm layer surrounding the embryo plays a crucial role in maintaining dormancy, and transcriptomics approaches are uncovering endosperm-specific genes and processes. Hormone signaling pathways have been extensively studied, but hormone-independent pathways and natural variation in key regulatory loci are also important. Environmental signals, particularly light, and moist chilling (stratification) are increasingly understood at the molecular level. The review highlights the importance of postgenomics, physiology, and molecular genetics in understanding these processes.