<p>Marchantia polymorpha is a common species in liverwort (Marchantiophyta) that occupies the basalmost lineage of land plant evolution. M. polymorpha has a long history as a model plant, and the state-of-the-art drawings of those days were published for education in late 19th century. As the gametophyte generation (n) dominates over the sporophyte generation (2n) in the life cycle, it is simple and efficient to take genetic approaches with M. polymorpha. The genome project that is in progress in Joint Genome Institute, U.S.A., with international collaboration including Japanese laboratories. M. polymorpha has relatively a simple genome context with low genetic redundancy and with fewer repetitive sequences, but possesses most genes for genetic regulatory networks that are common to other groups of land plants. With rapid and efficient methods of Agrobacterium-mediated transformation to sporelings and thalli, various molecular approaches for functional analysis of genes, including T-DNA tagging, expression modification, homologous recombination, genome editing and conditional expression, are available for research. M. polymorpha should offer a unique experimental platform to study the evolution and logics of regulatory systems in land plants.</p>