An understanding of basic methods in Arabidopsis tissue culture is beneficial for any laboratory working on this model plant. Tissue culture refers to the aseptic growth of cells, organs, or plants in a controlled environment, in which physical, nutrient, and hormonal conditions can all be easily manipulated and monitored. The methodology facilitates the production of a large number of plants that are genetically identical over a relatively short growth period. Techniques, including callus production, cell suspension cultures, and plant regeneration, are all indispensable tools for the study of cellular biochemical and molecular processes. Plant regeneration is a key technology for successful stable plant transformation, while cell suspension cultures can be exploited for metabolite profiling and mining. In this chapter we report methods for the successful and highly efficient in vitro regeneration of plants and production of stable cell suspension lines from leaf explants of both Arabidopsis thaliana and Arabidopsis halleri.