Hieroglyphic Jambs might be earlier than any other group of structures, and structures 5D1 and 5D3 nearby also might be early constructions. Some of the buildings at the Group of the Bird Cornice have features that seem to be early, but the evidence is slightly less convincing than that for the Group of the Hieroglyphic Jambs. Unfortunately in the two largest clusters, the Group of the Initial Series and the Southwest Group, it is difficult to state which structures are the earliest, and more specifically how early any building might be. The general chronological picture that emerges from analysis of the outlying groups suggests sporadic construction at the time of the earliest developments in the area of the main plaza. As the pace of construction increased around the main plaza, it also increased in the outlying groups during what for the moment may loosely be termed the middle period in the history of Modified Florescent Chichén Itzá. Study of the outlying groups sustains the view of progressive architectural decline at Chichén Itzá. Increasing reuse of earlier material in later structures combined with indifference to the quality of construction supports this conclusion. Examples include some of the structures of the Northwest Group, possibly the Temple of the Sculptured Jambs (4B1), and certainly the Temple of the Initial Series. This probably represents a late and final architectural phase at Chichén Itzá not represented by major constructions in the central sections. Maybe Chichén builders simply would not countenance such shoddy building practices in the central sections even while it occurred in the outlying groups. However, the final architectural phase at the site is probably best seen in the outlying groups, exemplified by the Initial Series Temple, while in the central section only certain patchwork jobs occurred, such as the construction of secondary walls inside some of the buildings. In general, although quite early constructions in the outlying groups were sporadic or nonexistent, by the time of the greatest architectural activity in the central section, building in the outlying groups was also in full swing. Construction in the outlying groups probably continued for a time after major building on the Court of the Columns ceased.