CRISPR systems have revolutionized life science research, therapeutic development, and agriculture by enabling the precise modification of nuclear genes in eukaryotic cells. However, in addition to nuclear DNA, eukaryotic cells also contain DNA within mitochondria and chloroplasts. Editing these organellar genomes remains a major challenge due to the difficulty of delivering CRISPR guide RNAs into these compartments. This limitation has hindered both basic and applied research on these essential organelles, which are responsible for oxidative phosphorylation and photosynthesis, respectively. Our research aims to overcome this barrier by developing advanced techniques for editing organellar DNA in cultured cells and whole organisms.