The importance of astronomy in the Maya civilization is well established from the codices and from the inscriptions found on the steles and other ceremonial monuments. The astronomy in the Maya codices is described with lots of details in the present chapter. The alignment of ancient monuments on the positions of the Sun at the time of the solstices and equinoxes is also considered. The extreme positions of certain planets, or the absolute value of their declination is also discussed. For the Maya, Venus was one of the most important celestial bodies but the observation of the Moon was also primordial. The Maya considered the architectural space in order to track the movements of celestial bodies and, in accordance with this process, create hierophanies. A widely held idea in the Maya civilizations was that leaders were believed to be responsible for the correct unfolding of cyclical changes in the natural environment. Correct and orderly planning of agricultural work during an annual cycle could be carried out using astronomical knowledge and was likely to contribute to developing more effective livelihood strategies and also to strengthening the legitimization of the power of the ruling class. As a more efficient distribution of activities in agricultural cycles ensured increased productivity and better living conditions, the professional skills of astronomer-priests were vital as they contributed to a prosperous economy.