Archaeological material from Kodiak Island, Alaska, is described in terms of five phases which, from oldest to youngest, are Ocean Bay I, Ocean Bay II, Old Kiavak, Three Saints, and Koniag. Ocean Bay I and II, components of a single site, are characterized by flaked-stone and ground-slate industries, respectively. Old Kiavak and Three Saints appear to be developmental stages within a single tradition, possibly different from the traditions of the antecedent Ocean Bay phases and the succeeding Koniag. In Old Kiavak there is a partial return to flaking of stone artifacts, and two characteristic artifacts are small notched stones and plummet-type grooved stones. In the Three Saints phase, "plummets" went out of use, and by the beginning of the Koniag phase, which continued into the contact period, so did small notched stones. Among the new elements that characterized the Koniag phase are the steam sweat bath, the splitting adz, and, locally, pottery. A pottery-using variant of this phase has been emphasized. When compared with Three Saints material, Koniag archaeological remains usually show style changes or degeneration in workmanship. These units do not outline a complete sequence because the periods between Ocean Bay II and Old Kiavak and, locally, between Three Saints and the pottery-using Koniag variant do not appear to be represented. It is estimated that their time range is 2500 B.C. to shortly after A.D. 1800.