Hopi religious life is ordered by a ceremonial calendar that divides the year in two, and by the clans and societies that own the parts of it. From the winter solstice observance through to the middle of the year the katsinam, spirit beings understood to come to the villages, are present, and their season closes with the Niman ceremony in July. The second half of the year belongs to societies whose ceremonies do not involve them, among them the Snake and Antelope societies and the women's societies.
Ceremonies belong to particular clans and societies rather than to the people at large. A named clan holds a given ceremony, is responsible for performing it correctly, and holds the right to decide who may take part in it and who may see it. That distribution of ownership is the central fact of Hopi religion, and it is the reason no account written from outside can be authoritative about the whole.
The atlas does not reproduce katsina imagery, and no katsina is drawn here. The Hopi Tribe, through its Cultural Preservation Office, has asked publicly and repeatedly that katsinam and katsina imagery not be reproduced, sold or displayed away from the context that holds them, and that request covers copying and invention equally. What is recorded here is what the katsinam are understood to be, who holds them, and the place they keep in the ceremonial year.