An interest in the Lalonde period of the Ontario Iroquois tradition became the motivation behind this preliminary excavation of the Baumann, site, Medonte Township, Simcoe County, Ontario. Excavation was followed by detailed analyses of the various cultural categories that comprise the site's assemblage. -- Although Lalonde has been recognized as part of the Late Ontario Iroquois Stage (Wright, 1966), only one other Lalonde site has been examined beyond the point of producing a rimsherd analysis; the Copeland site (Channen and Clarke, 1965), also in Simcoe County, Ontario. Frank Ridley, in presenting data from the Lalonde site (1952a), as well as Fallis (1952b), and Frank Bay (1954), describes the artifacts recovered. Settlement, floral, and faunal date are, however, not available, as is the case with quantitative information. The emphasis in all three reports is definitely on ceramics. This can be said of Latta's (1968) examination of Ontario prehistory as well, wherein two further Lalonde sites, Deschambault and Farlain Lake, are introduced. Also included in this analysis are those sites surveyed by Ridley (1966, 1967, 1969, 1971, 1973) which number over 40. - It was felt that because a Lalonde group of sites is implicitly understood to represent a part of Ontario prehistory, more than simply one site of this period needed to be studied in detail, and thus the Baumann excavation took place. - Excavation was not only done to buttress the existing chronological framework, but also to begin to attain an understanding of Lalonde culture. Thus, research goals included obtaining settlement data, floral, faunal, lithic, bone artifact, ceramic, and subsistence data. This information was then combined with any available comparative data to arrive at a cultural description of Lalonde. -- The six week excavation of this site resulted in the following: One midden was thoroughly tested, while the locations of three others were confirmed; a single longhouse was partially uncovered, measuring 66m x 8m having a rich feature assemblage and a northeast-southwest orientation; possible evidence of a second longhouse was uncovered in a test trench south of House 1; and, an attribute analysis of rimsherds revealed seven attributes which may be characteristic of the Lalonde ceramic assemblage; lastly, a C14 date (N.M.C.1222) of A.D. 1490 +/- 60 was obtained from a sample of charred wood. - Excavation of the Baumann site was conducted during the summer months of 1980 under License no. 80-F-0387 of the Ministry of Culture and Recreation, Provincial Government of Ontario, and funded by the Ontario Heritage Foundation