This book comprehensively describes the transgenesis techniques and applied experimental methods in ascidians including enthusiastically developed original devices in addition to concrete examples of developmental biology studies. Ascidians have been one of the most important model animals in developmental biology for studying molecular and cellular processes underlying formation of the chordate body plan. Transgenic techniques such as microinjection, electropolation, cis-element analysis and application, and TALENs and CRISPR/Cas9 have been developed in ascidians for more than 20 years, and now many applied methods, some of which are unique in ascidians, have been accumulated. Those extensive technological innovations, such as cell isolation, cell labeling, germ-line transformation, marker transgenic