This digital resource is a comprehensive manual from Roche, detailing protocols for non-radioactive in situ hybridization (ISH). Non-radioactive ISH methods offer a safer and often faster alternative to traditional radioactive ISH, utilizing chromogenic or fluorescent detection systems. This manual provides detailed guidance for researchers to perform ISH experiments without the need for radioactive isotopes. The manual covers various aspects of non-radioactive ISH, including sample preparation (tissue fixation, sectioning), probe labeling (e.g., with digoxigenin, biotin), hybridization conditions, washing steps, and signal detection using enzyme-conjugated antibodies or streptavidin. It likely includes troubleshooting tips and optimization strategies to ensure successful and sensitive detection of target nucleic acids (mRNA or DNA) within cells and tissues. Researchers in molecular biology, developmental biology, and pathology can benefit significantly from this manual. It enables them to visualize gene expression patterns or localize specific DNA sequences with high spatial resolution, providing crucial insights into cellular function and disease mechanisms. The non-radioactive approach makes the technique more accessible and suitable for routine laboratory use. As a product of Roche, a major life science company, the manual is expected to be thoroughly validated and reliable, reflecting best practices in the field. It serves as an essential reference for laboratories implementing or optimizing non-radioactive in situ hybridization techniques, ensuring robust and reproducible results.