In recent decades, the application of new molecular and cellular techniques in avian embryos has opened up new avenues to understanding various biological questions in birds, including chickens (Gallus gallus). Questions include, how cells grow, migrate, differentiate, and function, and how birds behave. These techniques may also be beneficial to existing industries, such as poultry and medicine. For example, emerging single-cell RNA sequencing and related multimodal molecular approaches have led to the description of new cell types and their states. Electroporation, viral vectors, and ever-improving genome editing methods using CRISPR, have allowed us to inquire into the functions of particular genes and visualize specific cell populations in tissues and animals. Chicken eggs are also essential resources for the production of IgY antibodies and vaccines for infectious diseases. This Methods Collection will focus on new techniques with which to study chicken or other avian embryos.