Eds. Manuel Domínguez-Rodrigo, Luis Alcalá, and Luis Luque. Table of contents: 1. Structural and Referential Principles as Applied to Research Design at Peninj (Manuel Dominguez-Rodrigo and Luis Alcala) 2. The Peninj Group: Tectonics, Volcanism, and Sedimentary Paleoenvironments During the Lower Pleistocene in the Lake Natron Basin (Tanzania) (Luis Luque, Luis Alcala¡, and Manuel Dominguez-Rodrigo) 3. The Peninj Group in Type Section (Maritanane): An Analysis of Landscape Evolution (Luis Luque, Luis Alcala, and Manuel Dominguez- Rodrigo) 4. A Taphonomic Study of the T1 Paleosurface in Type Section (Maritanane): The ST Site Complex (Manuel Dominguez-Rodrigo, Luis Alcala, and Luis Luque) 5. Isotopic Ecology and Diets of Fossil Fauna from the T-1 (Type Section, Maritanane) Paleosurface (Nikolaas J. van der Merwe) 6. Archaeological Evidence of Carcass-Processing Spots Created by Lower Pleistocene Hominids from the ST4 Site (Manuel Dominguez-Rodrigo, Fernando Diez-Martin, Luis Alcala, Luis Luque, Rebeca Barba, Rafael Mora, Ignacio de la Torre, and Pastory Bushozi) 7. The Technology of the ST Site Complex (Ignacio de la Torre and Rafael Mora) 8. ST-69: An Acheulean Assemblage in the Moinik Formation of Type Section (Fernando Diez-Martin, Luis Luque, and Manuel Dominguez-Rodrigo) 9. The Acheulian Sites from the South Escarpment (Manuel Dominguez- Rodrigo, Jordi Serrallonga, Luis Luque, Fernando Diez-Martin, Luis Alcala, and Pastory Bushozi) 10. The Acheulian Sites from the North Escarpment (Manuel Dominguez- Rodrigo, Fernando Diez-Martin, Luis Luque, Luis Alcala, and Pastory Bushozi) 11. Conclusions (Manuel Dominguez-Rodrigo, Luis Alca la, and Luis Luque)