In the spring of 1947 R. L. Beals, of the University of California, Los Angeles, and R. F. Heizer, of the University of California, Berkeley, agreed to sent a joint party into the field the following summer. This coöperation between the two institutions marked a new step in furthering the progress of archaeological research in California, and gave students an opportunity to participate in active field research. In June, 1947, the senior author, assisted by Miss Consuelo Malamud, a graduate student at UCLA, initiated excavation at the Tank Site. Undergraduate and graduate students from both campuses of the university as well as from San Francisco State College acted as volunteer workers. The results of this investigation have appeared under the title, "The Topanga Culture: First Season's Excavation of the Tank Site, 1947" (Treganza and Malamud, 1950). The activities of the first season should have brought to light a fairly representative sample from the site, but time imposed certain limitations, and much of what was uncovered only added to the list of problems. Further, the Tank Site as a unit was, presumably, known with some certainty, but there was little comparative material in which to frame the results. Therefore, three major lines of evidence remained to be investigated: (1) Additional excavation was necessary to verify the possible stratigraphy noted and to fill out the burial data and certify the typology established on the basis of the finds to date. Moreover, the Tank Site had demonstrated itself to be a deposit of unusual interest and importance; whatever added knowledge could be gained from it would be valuable. (2) LAn-2, just west of the Tank Site, required more intensive examination. From surface collections and test pits it was apparent that this site afforded clues to the interpretation and extension of the stratigraphy noted at the Tank Site, and it might represent a cultural development heretofore undescribed for the area. (3) A survey of the canyon should be undertaken so that the Topanga Culture could be viewed beyond its narrowly known confines. The problem was to gain an estimate of the number of lithic sites within the canyon drainage, and the points of similarity and difference between these and the Tank Site. With the above three problems in mind, archaeological investigations were renewed in Topanga Canyon on the same coöperative basis as the previous year. We are indebted to the following students, drawn from the three state institutions mentioned above, for volunteering their time and energies in behalf of the project: Richard Bachenheimer, Alan Beals, Hal Eberhart, Robert Farrell, David Frederickson, William King, Harland Kinsey, Joseph Kreisler, Donald Lathrap, Albert Mohr, Arnold Pilling, and Barbara Wyman. The authors acted, respectively, as field director and assistant field director. Agnes Bierman and Albert Mohr are responsible for most of the field photography, mapping, and surveying.