Ammonia is promoted as a potential alternative fuel due to its no carbon emissions. Obtaining laminar flame speed at high pressure and temperature for near stoichiometric conditions is important for engine sizing. A wide range of experimental conditions have been explored along with the evaluation of the most recent kinetic mechanisms. It is also interesting to study the inner structure of the premixed ammonia flame at standard conditions to understand the combustion process and to precisely determine the flame speed. For thick flames, the isotherm selection plays a major role.